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Automobile Electrical and Electronic SystemsThird edition This page intentionally left blank Automobile Electrica. Automobile Electrical and Electronic Systems PDF Book Free Automotive Embedded Systems HandBook PDF · Automobile Chassis and Body Engineering . Electronic Systems. Third Edition. List of Chapters. Preface. Introduction to the third edition. Acknowledgements. 1. Development of the automobile electrical.

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This textbook will help you learn all the skills you need to pass Level 3 Vehicle Electrical and Electronic Systems courses or related modules from City and. Ebook BookK Automobile Electrical and Electronic Systems Tom Denton [ DOWNLOAD] PDF - Tom Denton - [Free] PDF Download Here. the fourth edition of this book! Language: English Format: PDF Size: Mb. Automobile Electrical and Electronic Systems PDF free download scr1.

Hit a particularly tricky question? Bookmark it to easily review again before an exam. The best part? As a Chegg Study subscriber, you can view available interactive solutions manuals for each of your classes for one low monthly price. Why buy extra books when you can get all the homework help you need in one place? Can I get help with questions outside of textbook solution manuals? You bet! Just post a question you need help with, and one of our experts will provide a custom solution. You can also find solutions immediately by searching the millions of fully answered study questions in our archive.

How do I view solution manuals on my smartphone? So who discovered electricity? Ben Franklin? Thomas Edison figured out how to use electricity to make light bulbs.

Next we take one of the halves and divide it into two parts. There are many different kinds of matter. We use it every day. Other elements have been produced only in the laboratory. A hydrogen atom Figure contains one proton. Scientists have discovered many particles in the atom. The structure of the atom resembles planets in orbit around a sun. William Gilbert published a book describing these phenomena. An atom is so small that it cannot be seen with a conventional microscope. Most have been found in nature.

Some of our pieces would have the characteristics of copper. Each element is a type of matter that has certain individual characteristics. In Every material we know is made up of one or more elements. But what exactly is electricity? Others would show themselves to be carbon.

An atom is itself made up of smaller particles. All the atoms of any particular element look essentially the same. He also discovered that other materials shared the ability to attract. An atom is the smallest particle that has the characteristic of the element. Orbiting around the nucleus. Atoms If you could keep dividing the material indefinitely. Two thousand years after ancient Greece.

Then we test both halves to see if it still has the same characteristics. All atoms share the same basic structure. One force comes from electrical charges and the other force. The charges within an atom.

The term electricity is used to describe the behavior of these electrons in the outer orbits of the atoms. Inside each atom. The nucleus contains the proton and the neutron. Electrical Charges Neutrons have no charge. Instead of being electrically neutral. This means the atom is electrically neutral or balanced because there are exactly as many negative charges as there are positive charges. If anything upsets that balance. Unlike and like charges of a magnet.

Like electrical charges always repel. If an atom loses one electron. All electrons and protons are alike. The greater the speed. As a result. The number of protons associated with the nucleus of an atom identifies it as a specific element. Protons carry a positive electrical charge Figure All elements are composed of atoms and each element has its own characteristic number of protons with a corresponding equal number of electrons.

Electrons orbit the nucleus of an atom in a concentric ring known as a shell. Electrons have 0. There are two types of force at work in every atom. In its normal state.

In an atom left. The electrons are in different shells or distances from the nucleus. Under normal conditions. It is possible for an atom to lose or gain electrons. Introduction to Electricity 23 Figure Opposite electrical charges always attract one another.

Copper Atom Figure Any atom may possess more or fewer electrons than protons. The heaviest elements in their normal states have only the first four shells fully occupied with electrons. A balanced atom. Ions try to regain their balance of equal protons and electrons by exchanging electrons with nearby atoms. Valence represents the ability to combine. An atom of the element neon with an atomic number of 10 has both a full first and second shell 2 and 8: When this potential or pressure causes a number of electrons to move in a single direction.

The number of electrons in the valence ring will dictate some basic characteristics of an element. The most complex atoms may have seven shells.

This is known as the flow of electric current or electricity. For more information about voltage and current. This difference in electric potential is more commonly known as voltage and can be compared to a difference in pressure that makes water flow.

The simplest element. So the definition of current is the flow of electrons. An unbalanced atom. The chemical properties of atoms are defined by how the shells are occupied with electrons. An ion is an atom that has gained or lost an electron. Other more complex atoms that have eight electrons in their outermost shell. Valence ring. An atom of the element helium whose atomic number is 2 has a full inner shell.

The outermost shell in any atom is known as its valence ring. Electrons resting on a surface will cause it to be negatively charged.

Remember that an ion is any atom with either a surplus or deficit of electrons. Valence The concentric orbital paths. The electrons in the shells closest to the nucleus of the atom are held most tightly while those in the outermost shell are held more loosely. Free electrons can rest on a surface or travel through matter or a vacuum at close to the speed of light. Such an unbalanced atom would be described as negatively an excess of electrons or positively a net deficit of electrons charged and known as an ion Figure The maximum number of electrons that can occupy shells one through seven are.

Single Valence Electron Figure Introduction to Electricity 25 Because the electrons are not moving. Current flow is measured in amperes: For instance. In the early s. The extent of the charge is measured in voltage or charge differential.

Franklin was trying to prove that the positive and negative electron distribution in the clouds produced the static electricity that causes lightning. Benjamin Franklin. Natural negatively charged particles will produce lightning when they find a path negative to positive. He also thought that electricity was like a fluid in a pipe that flowed from one terminal to the other. He named the electrical terminals positive and negative and suggested that current moved from the positive terminal to the negative terminal.

Although he was not the first to think that electricity and lightning were the same. When the science of electricity was still young. A stream of moving electrons is known as an electrical current. Static electricity is an everyday phenomenon. Taken all together. The extent of the charge differential is. Static electricity can also be referred to as frictional electricity because it results from the contact of two surfaces.

An automotive technician should always use a static grounding strap when working with static-sensitive electronic devices such as PCMs and ECMs. It is referred to as static electricity because. Static electricity discharge attraction. Chemical bonds are formed when any surfaces contact and if the atoms on one surface tend to hold electrons more tightly.

Electrostatic Field The attraction between opposing electrical charges does not require contact between the objects involved. The static charges that build up are not discharged until a conductor. This is so because invisible lines of force exist around a charged object. Static can be created by any one of the following examples: Such contact produces a charge imbalance by pulling electrons of one surface from that of the other.

While the surfaces with opposite charges remain separate. Such fields are strongest very close to the charged object and get weaker as they extend away from the object. When the two polarities of charge are united. Static electricity discharge to metal object. Static Electricity Static electricity is the term used to describe an electrical charge that can build up in insulation by friction or movement.

The charges created can be shown as in Figure When the battery is connected into a completed electrical circuit.

At the same time. This current is produced by chemical reactions between the active materials in the two kinds of plates and the sulfuric acid in the electrolyte Figure Chemical Source A battery creates electricity by chemical reaction by the lead dioxide and lead plates submerged in a sulfuric acid electrolyte.

Electrostatic field. This is called electrostatic discharge ESD. Introduction to Electricity 27 Figure The lead dioxide in the positive plate is a compound of lead and oxygen. Sulfuric acid is a compound of hydrogen and the sulfate radical. In the case of automotive battery.

Figure shows what the ESD symbol looks like. During discharge. Automotive battery operation. The symbol tells you that the component is a solid-state component. If you touch something. We will cover this subject in detail in Chapter 10 of this manual. Look for these indicators and take the suggested ESD precautions when you work on sensitive components.

In any battery. ESD symbol. An electrolyte is a chemical solution that usually includes water and other compounds that conduct electricity. The voltmeter can then be calibrated in degrees. Photoelectricity is used in photoelectric cells. After most of the available active materials have reacted.

Solar energy is light energy from the sun that is gathered in a photovoltaic solar cell. A pyrometer is commonly used to measure exhaust gas temperatures on diesel engines and other temperature measuring applications.

As the temperature at the connections of the two metals increases. Photoelectricity shows a very simplified version of a battery powered by a lemon. Light is composed of particles called photons that are pure energy and contain no mass.

Figure shows that when these materials. The typical knock sensor Figure produces about millivolts of electricity and vibrates at a 6. Pyrometer thermocouple. A pyrometer is constructed of two dissimilar metals. Lemon powered battery. This affect was discovered by a German scientist named Seebeck and is known as the Seebeck Effect.

Piezoelectricity Thermoelectricity Applying heat to the connection point of two dissimilar metals can create electron flow electricity.

A change in the potential of electrons between the positive and negative terminal creates electricity know as piezoelectricity. An example of a thermocouple is a temperature measuring device called a pyrometer. Lemon Battery Figure Piezoelectricity is the principle used in knock sensors KS. The availability and amount of electrical energy that can be produced in this manner is limited by the active area and weight of the materials in the plates and by the quantity of sulfuric acid in the electrolyte.

Seebeck called this device a thermocouple. Applying a high-frequency alternating voltage to a crystal can create a reverse piezoelectric effect. Introduction to Electricity 29 Figure Piezoelectric knock sensor. Similar applications are used in underwater hydrophones and piezoelectric stethoscopes. Piezoelectricity is put to practical use in phonograph pickups and crystal microphones.

Although the effect is only temporary. The crystal then produces mechanical vibrations at the same frequency. Squeeze a Rock Get a Volt In Piezoelectric effect.

Photoelectric cell sensor. Joseph Priestly established that electrical charges attract with a force inversely proportional to distance. Alessandro Volta invented the first battery. This provided a means of introducing electrical power into industry and the home. These ultrasonic vibrations are used. One horsepower is needed to lift pounds 1 foot off the ground in 1 second. The term brake horsepower comes from the method of testing the early engines. Horsepower can also be expressed in units of electrical power or watts.

The German physicist George Simon Ohm — proved the mathematical relationship between electrical potential voltage. Andre Marie Ampere established the importance of the relationship between electricity and magnetism. Thomas Edison — invented the incandescent lamp in In the metric system. Electricity is sold in kilowatt hours. A watt light bulb requires more electrical power to light than a 60watt bulb. Alessandro Volta discovered that if two dissimilar metals were brought in contact with a salt solution.

Thomson — in introduced the science of electronics and quickly resulted in the invention of the diode Another person who influenced electrical technology was a Scottish inventor named James Watt — He developed the steam engine to take over the task of lifting heavy loads instead of using the power of a horse.

The term watt is most commonly used to express electrical power. The discovery of the electron by J. Michael Faraday — opened the doors of the science we now know as electromagnetism when he published his law of induction. A light bulb is an example of where watts are commonly used.

A kilowatt is watts and a kilowatt hour is one kilowatt of power being used for one hour. An electrostatic charge can build up on the surface of your body. The phenomenon we describe as electricity concerns the behavior of atoms that have become. When light contacts certain materials. A photon is pure energy that contains no mass. Static electricity is electricity at rest or without any motion.

All matter is composed of atoms and electrical charge is a component of all atoms. An automotive technician should always use a static grounding strap when working with staticsensitive electronic devices.

The production of electricity from chemical energy is demonstrated in the lead-acid battery. Piezoelectricity is electricity produced when materials such as quartz or barium titanate are placed under pressure. An atom is the smallest part of an element that retains all of the properties of that element. Thermoelectricity is electricity produced when two dissimilar metals are heated to generate an electrical voltage. Solar energy is light energy photons from the sun that is gathered in a photovoltaic solar cell.

Electromagnetic induction is the production of electricity when a current is carried through a conductor and a magnetic field is produced. When an atom is balanced. Electricity may be defined as the movement of free electrons from one atom to another. George Simon Ohm showed a relationship between resistance.

Introduction to Electricity 31 SUMMARY The Greeks discovered the first type of electricity in the form of static electricity when they observed that amber rubbed with fur would attract lightweight objects such as feathers. A thermocouple is a small device made of two dissimilar metals that gives off a low voltage when heated.

Technician B says an electrostatic charge can build up on the surface of your body. Technician A says it is electricity produced when barium titanate is placed under pressure. Atom b. Technician B says the battery stores energy in a chemical form.

Neither A nor B Both A and B d. Compound d. An atom that loses or gains one electron is called which of the following: Molecules c. Technician B says that an electrolyte is a chemical solution of water and hydrochloric acid that will conduct electricity.

Automobile Electrical and Electronic Systems

Protons 4. A only b. Technician A says applying heat to the connection point of two dissimilar metals can create electron flow electricity. What people discovered electricity? The Germans c.

B only c. Neither A nor B 6. Nucleus 2. Electrons b.

The Irish 8. Technician A says that static electricity is electricity in motion. Nucleus d. The smallest part of an element that retains all of its characteristics is which of the following: An element c. Technician A says the battery provides electricity by releasing free electrons.

Balanced b. Who is right? Technician B says one horsepower would be produced when a horse walked feet in one minute pulling. An ion 5. Technician A says when sunlight contacts certain materials.

Technician B says when no change in the potential of electrons between positive and negative terminal occurs. Matter c. Neither A nor B 9. Neutron 3. Two technicians are discussing how piezoelectricity works.

The general name given every substance in the physical universe is which of the following: The Italians b. Static electricity is being discussed. The Greeks d. The particles that orbit around the center of an atom are called which of the following: Proton c.

Technician B says solar energy is light energy from the moon that is gathered in a photovoltaic solar cell. Technician A says one horsepower equals Technician A says batteries produce direct current from a chemical reaction. Two technicians are discussing thermoelectricity. Mass b. Neither A nor B 7. A molecule d.

Technician B says a thermocouple is a small device made of two dissimilar metals that gives off a low voltage when heated. Technician B says Alessandro Volta discovered that if two dissimilar metals were brought in contact with a water solution. Introduction to Electricity 33 a pound weight or ft. Neither A nor B. Technician A says Andre Marie Ampere established the importance of the relationship between electricity and magnetism. An automotive technician must have a thorough grasp of the basis of electricity Define the two theories of current flow conventional and electron and explain the difference between DC and AC current.

Define capacitance and describe the function of a capacitor in an automotive electrical circuit. Identify and explain the basic electrical concepts of resistance. Normally the nucleus does not change. Copper is the conductor most used in vehicles because the price of copper is reasonable compared to the relative cost of other conductors with similar properties.

Conductors and insulators. This is so because the electrons in the conductor affect one another. These materials are called insulators.

When voltage is applied to a disconnected length of wire open circuit. The metal core of the wire. Some materials hold their electrons very tightly. This orbit is far enough away from the nucleus of the copper atom that the pull or force holding the outermost electron in orbit is relatively weak. But some of the outer electrons are held very loosely.

If voltage is applied to one end of a conductor. Yet when an electrical potential is applied to one end of a wire.

Wires A wire in a wiring harness is made up of a conductor and an insulator. In a typical automotive circuit. The outer jacket made of plastic or other material coating the core is the insulator. The protons and neutrons in the nucleus are held together very tightly. Electronics has become the single most important subject area and the days when many technicians could avoid working on an electrical circuit through an entire career are long past.

No current flows in the wire. An atom that gains electrons has more negative than positive particles. Check the voltage with a meter. Conductors are materials with four electrons in their outer orbit.

A charged atom is called an ion. Under normal circumstances. This course of electrical study will cover conductors and insulators. Copper is an excellent conductor because it has only one electron in its outer orbit.

An atom that loses electrons has more positive charges protons than negative charges electrons. Materials with exactly four electrons in their outer orbit are neither conductors nor insulators and are called semiconductor materials. Examples of insulators include plastics. Electrons are negatively charged and unlike charges attract. Current flow. Voltage pushes current flow like force pushes water flow. A current flow of 6.

This unit expresses how many electrons move through a circuit in one second. Another way of describing current flow is called the electron theory. Current The movement of electrons in a circuit is the flow of electricity. Voltage and water pressure. The conventional theory and electron theory are two different ways of describing the same current flow. This way of describing current flow is called the conventional theory.

A coulomb is 6. Charge differential exists when the electrical source has a deficit of electrons and therefore is positively charged. The important thing to know is which theory is being used by the service literature you Current Flow Current flow will occur only if there is a path and a difference in electrical potential.

Voltage is a potential difference in electromotive force. The electron theory follows the logic that electrons move from an area of many electrons negative charge to one of few electrons positive charge.

Automobile Electrical And Electronic Systems Tom Denton

A cycle is one complete reversal of current from zero though positive to negative and back to the zero point. This type of current is called alternating current or AC Figure Alternating Current The electrical potential created by a generator is not steady state.

The frequency at which the current alternates is measured in cycles. In residential electrical systems. We call that direct current or DC Figure When such a potential is applied to a circuit. Resistance More vehicles can travel on a four-lane superhighway in a given amount of time than on a two-lane country road.

Automotive generators produce AC potential. The physical dimensions of a conductor are also a factor. A large-diameter pipe can flow more fluid than a small-diameter pipe. Alternating current. Direct current. A similar characteristic applies to electricity.

This results in a flow of electrons through the conductor from the negative charge to the positive charge. Alternating current is also better suited than DC for transmission through power lines. A conductor. Direct Current When a steady-state electrical potential is applied to a circuit.

A large wire can carry. The advantage of using DC is it can be stored electro-chemically in a battery. TIME happen to be using. The charge differential or voltage is a measure of electrical pressure. Rotating a coil in a magnetic field usually produces alternating current. When an external power source such as a battery is connected to the conductor. Alternating current is easier to produce in a generator.

Alternating current describes a flow of electrical charge that cyclically reverses. The larger the cross-sectional area measured by wire gauge size the more atoms there are over a given sectional area. Batteries produce a steady-state.

The role of a battery. In a closed electrical circuit. Frequency is usually measured in cycles per second or hertz. Resistance factors Figure determine the resistance of a conductor by a combination of the following: The more free electrons a material has. Resistance opposes the movement of electrons. For most materials.

Resistors Resistors are devices used to provide specific values of resistance in electrical circuits. We use it to produce heat. A common type is the carbon-composition resistor. Sometimes you can predict that high unwanted resistance is present by just looking at an electrical connection or component. All electrical devices and wires have some resistance. The reason the large wire carries more current is that it offers less resistance to current flow.

Broken Ohms The basic unit of measurement for resistance is the ohm. For example: The larger the cross-sectional area of a conductor. The condition of a conductor can also have a large affect on its resistance Figure Wanted and Unwanted Resistance Resistance is useful in electrical circuits.

Expect resistance to be high if the material is discolored or if a connection appears loose. Materials with very low resistance are called conductors. This makes the terminal a less effective conductor. The longer a conductor. If the resistance of a material is low close to zero ohms.

Resistance can also be affected by the physical condition of a conductor. If the resistance of a material is high close to infinite ohms. All materials contain some resistance. There are a few materials whose resistance goes down as temperature goes up. As resistance works to oppose current flow. For information about measuring resistance. We usually call a break in a circuit an open. Current flows only in a closed or completed circuit.

The battery is an electrochemical device. Electrolyte is made from water and sulfuric acid. Resistance factors.

These elements are connected to each other with conductors. The primary power source in a car or truck is the battery. Most protection circuits contain a source of power.

Once an external connection is made between them. In other words. Current flows from one end of a circuit to the other when the ends are connected to opposite charges positive and negative We usually call these ends power and ground.

As long as there is no external connection between the positive and negative sides. A circuit is a path for electric current. The size of the resistor determines how much heat the device can dissipate.

It has a positive side and a negative side. A pasty chemical called electrolyte is used as a conductor between the positive and negative parts. If there is a break somewhere in the circuit.

The negative part of the battery is made up of sponge lead. A circuit may be connected to ground with a wire or through the case of a component.

Most vehicles today use a negative ground system. When a component is case-grounded. Voltage drop is the voltage lost or consumed as current moves through resistance.

Negative or Positive Ground Circuits can use a negative or a positive ground. Current Flow Current Flow The complete electrical circuit. In a refrigerant circuit. Control devices can be on the positive or negative side of the circuit. All loads offer some resistance to current flow. Voltage is highest where the conductor connects to the voltage source. Controls used to vary the rate include rheostats. The voltage change across the resistance is called a voltage drop Figure Conductive Material Conductive materials.

Control devices work by completely stopping current flow or by varying the rate of flow. Controls used to stop current flow include switches. It can act as the ground for circuits throughout the vehicle. Ground In a closed circuit. In an automobile. If you measure voltage before it. We usually call the return side of the source the ground. Controls Control devices perform many different jobs. In this system. One ampere is equal to 6. This is voltage drop. This is the same as water pressure is measured in pounds per square inch or psi.

Current Electrical current is measured in amperes. For more information about measuring voltage. When you connect several conductors to each other. Operations Voltage drop. This unit would be the same as gallons per minute gpm of water flow if compared to water from a faucet.

George Simon Ohm.

This loss is voltage drop. Whenever the voltage applied to a device a load is less than the source voltage there is a resistance between the two components. Illustrating electrical units water makes the units of electricity easier to understand. Voltage drop is the result of a total applied voltage that is not equal at both ends of a single load circuit. The resistance in a circuit opposes the electron flow.

Voltage Voltage is the unit of electrical pressure. If this battery provides 1 volt of pressure. Just as water pressure is available at a faucet. An ampere is a unit of the amount of current flow.

If the known units are inserted into the equation. In the circuit in Figure The current flow through the circuit is 6 amps.

Since the amps are missing. Performing the multiplication in the equation yeilds in 12 volts. Since the volts are missing. Electrical Fundamentals 43 Resistance The unit of electrical resistance is the ohm. The equation is: R E I Figure A small water pipe can only allow so much water.

Here is an easy way to remember how to solve for any part of the equation: Solving for voltage. The resistance of the load in the circuit is 2 ohms. Solving for current. A large fire hose. Resistance in an electrical circuit creates heat because the increased number of collisions that occur between the free electrons and the vibrating atoms. When these collisions create heat. Resistance in the flow of water is usually associated with the size of the water pipe.

A closed circuit is a circuit that is complete and current is flowing.

Performing the division in the equation yields in 6 amps as the current flow in the circuit. The source voltage is 12 volts. An open circuit has a break somewhere and no current flows.

An ohm is the unit of electrical resistance. The remaining letters give the equation for determining the unknown quantity. In a complete electrical circuit. Solving the three columns mathematically.

Many electrical devices are rated by how much electrical power they consume. If the voltage increases Column 2. The output of automotive engines is usually expressed in horsepower. In both cases. If the resistance decreases Column 3. Power consumption is expressed in watts: Performing the division in the equation yields 2 ohms as the resistance in the circuit.

The amount of current can change only if the voltage or the conductor changes. Decrease the resistance to 3 ohms and keep the voltage at 12 volts: Solving for resistance.

In addition to showing what happens to current if voltage or resistance changes. Current never changes on its own—it changes only if voltage or resistance changes.

If the resistance increases Column 3. Power Formula We describe the relationships among power. This table can predict the effect of changes in voltage and resistance or it can predict the cause of changes in current. The basic equation for the Power Formula is as follows: If the voltage decreases Column 2. Decrease the voltage to 10 volts: If the resistance in a conductor increases or decreases.

Since the ohms are missing. Current cannot change on its own because voltage causes current through a conductor and all conductors have resistance.

If the total current I is equal to 10 amps. A simple capacitor. You know that the voltage in your home is about Multiply these two values and you get watts. In a circuit. The most common applications of ratings in watts are probably light bulbs. A capacitor Figure is a device that opposes a change in voltage. Capacitors are sometimes referred to as condensers because they do the same thing. If voltage or current decreases.

Electrical Fundamentals 45 Figure The property of opposing voltage change is called capacitance. You can multiply the voltage times the current in any circuit and find how much power is consumed. How fast this happens depends on several factors. The negative plate retains its accumulation of electrons. An electrostatic field exists between the capacitor plates. If a capacitor is placed in a circuit with a voltage source. No current flows in the circuit.

Actual construction methods vary. The charge is retained in the capacitor until the plates are connected to a lower-voltage electrical circuit. A capacitor is a device that opposes a change in voltage.

Typical dielectric materials are air. As the capacitor is charging. When the capacitor is charged. Electrons move in this way until the electrical charge of the capacitor is equal to that of the voltage source. In some circuits. An electrostatic field exists between the capacitor plates and no current flows in the circuit. When a capacitor is connected to an electrical power source. This is how the capacitor stores energy.

When capacitors provide electricity.More lines or a higher grade number indicate a stronger bolt. We will look at natural forms of electrical energy. Sulfuric acid is a compound of hydrogen and the sulfate radical. Which of the following causes voltage drop in a circuit?

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If a hydraulic circuit analogy is used to describe an electrical circuit. Static electricity can also be referred to as frictional electricity because it results from the contact of two surfaces. Hit a particularly tricky question? Chemical bonds are formed when any surfaces contact and if the atoms on one surface tend to hold electrons more tightly.

Published on May 31,

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