You throw a ball downward from a window at a speed of 1.7 m/s. How fast will it be moving when it hits the sidewalk 2.5 m below?

Answers

Answer 1

Answer:

7.43m/s

Explanation:

Given parameters:

Initial velocity = 1.7m/s

Height  = 2.5m

Unknown:

Final velocity  = ?

Solution:

To solve this problem, we apply one of the motion equation. The most fitting one given the parameters is;

           V²  = U² + 2gh

where V is the final velocity

           U is the initial velocity

          g is the acceleration due to gravity = 9.8m/s

           h is the height

Input the parameters and solve;

    V² = 2.5² + 2(9.8)(2.5)

    V = 7.43m/s


Related Questions

Describe and give an example of a normal force.

Answers

Answer:

Normal force is the force exerted on an object that is in contact with another non-moving object. Force is push and pull

Ex: When a book rests on a surface (like a table), the table is exerting a force on the book in order to support the weight of it.  

Answer:

Normal Force is a contact force. When 2 objects are touching each other, they are in contact. Like when a cup is sitting on a table they are in contact cause the table has to hold the force of the cup up on the table.

A example of normal force is when a book is sitting on a table, and the table is holding the force of the book up.

Explanation:

Hope this helps!!

Have a blessed day/night! <33

elastic limit is equal to:(a) stress (b)strain (c) young's modulus (d)modulus of rigidity

Answers

Answer:

A. stress

Explanation:

Hope this helped. Have an amazing day/night!!

We have that for the Question "elastic limit is equal to" it can be said that

Young's modulus

This speaks to a body retaining it shape after changes occur

Option C

From the question we are told

elastic limit is equal to

(a) stress

(b)strain

(c) young's modulus

(d)modulus of rigidity

Where

Where

Stress is the force acting on a material

and

strain

The effect of  force acting  on a material

Young's modulus

This speaks to a body retaining it shape after changes occur

Modulus of rigidity

m=sheer stress/shear strain

Now having that

Elastic limit is a point where an elastic body does not return to its original shape

The option chosen is'

Young's modulus

This speaks to a body retaining it shape after changes occur

Option C

Generally the equation for the   is mathematically given as

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A spherical balloon is inflated with gas at a rate of 800 cubic centimeters per minute. (a) How fast is the radius of the balloon changing at the instant the radius is 70 centimeters

Answers

Answer:

0.013 cm/minute

Explanation:

We are given;

Volume rate; dV/dt = 800 cm³/min

Now, volume of a sphere is given by the formula;

V = (4/3)πr³

We want to find the rate at which the radius of the balloon is changing. This is represented by dr/dt.

Now, dr/dt will be gotten from the relation;

dr/dt = dV/dt ÷ dV/dr

Now, dV/dr = 3 × (4/3)πr²

dV/dr = 4πr²

Thus;

dr/dt = 800/(4πr²)

At r = 70 cm

dr/dt = 800/(4π × 70²)

dr/dt = 0.013 cm/minute


40 m north west
50m Northwest
120 m southeast
40 m south east

Which answer

Answers

Answer:

120 north west

Explanation:

did he wash the shoe.change it to passive voice​

Answers

Answer:

Did he wash the shoes?-Were the shoes washed by him?

What has the least potential energy in this world

Answers

It would be a less heavy ball

Answer:

Anything that has the most kinetic has the least potential energy.

Explanation:

NEED BRAINLYEST PLZZ!!!!!!!!!!!!!!!

Two equal masses travel in opposite directions with equal speeds. They collide in a collision that is between elastic and inelastic. Just after the collision, their velocities are

Answers

Answer:

less in magnitude and opposite in direction to their original velocities

Explanation:

The nature of collisions can be determined by the coefficient of restitution.

Coefficient of restitution is given by

[tex]e=\dfrac{\text{Kinetic energy after collision}}{\text{Kinetic energy before collision}}[/tex]

In the case described here the value of [tex]e[/tex] is in between 0 and 1.

This means that the kinetic energy after collision is less than the kinetic energy before collision.

If the kinetic energy after collision is less this means that the velocity is not balanced with the velocity before the collision however the direction of the masses are opposite Some amount of energy is dissipated as heat or through other forms of energy.

So, just after the collision, their velocities are less in magnitude and opposite in direction to their original velocities.

A 227−lb fullback runs the 40−yd dash at a speed of 17.25 pm 0.10 mi/h. Enter your answers in scientific notation. (a) What is his de Broglie wavelength (in meters)? × 10 (select) m (b) What is the uncertainty in his position based on the de Broglie wavelength?

Answers

Answer:

His de Broglie wavelength is 8.35×10⁻³⁷ m

The uncertainty in his position is 1.15 × 10⁻³⁵ m

Explanation:

First, Convert 227-lb to kg and convert the unit of the speed from mi/h to m/s.

To convert 227-lb to kg,

1-lb = 0.453592 kg

∴ 227-lb = 227 ×  0.453592 kg

227-lb = 102.97 kg

To convert 17.25 ± 0.10 mi/h to m/s

1 mi = 1609.34 m

and 1 h = 3600 s

Therefore,

17.25 mi/h = (17.25 ×1609.34)/3600 m/s = 7.71 m/s

and 0.10 mi/h =  (0.10 ×1609.34)/3600 m/s = 0.044704 m/s

Hence, the speed 17.25 ± 0.10 mi/h = 7.71 ± 0.044704 m/s

Now

(a) To determine the de Broglie wavelength,

De Broglie wavelength is given by

λ = h/mv

Where λ is the de Broglie wavelength

h is Planck's constant (h = 6.626×10⁻³⁴ kgm²/s)

m is the mass

and v is the speed (velocity)

From the question

m = 102.97 kg

v = 7.71 m/s

Therefore,

λ = 6.626×10⁻³⁴ / (102.97×7.71)

λ = 8.35×10⁻³⁷ m

Hence, his de Broglie wavelength is 8.35×10⁻³⁷ m

(b) To calculate the uncertainty in his position

From

Δx = h/(4πmΔv)

Where Δx is the uncertainty in the position

h is Planck's constant (h = 6.626×10⁻³⁴ kgm²/s)

π is a constant ( π = 3.14)

m is the mass

Δv is the uncertainty in speed

From the question

m = 102.97 kg

Δv = 0.044704 m/s

Hence,

Δx = 6.626×10⁻³⁴  / (4×3.14×102.97×0.044704)

Δx = 1.15 × 10⁻³⁵ m

Hence, the uncertainty in his position is 1.15 × 10⁻³⁵ m.

An 80 N box initially at rest is pulled by a horizontal rope on a horizontal table. The coefficients of kinetic and static friction between the box and the table are 0.25 and 0.5 respectively. What is the friction force on this box if the pull is 25N?

A. 20 N
B. 40 N
C. 25 N
D. 0 N

Answers

Answer:

C. 25 N

Explanation:

w = Weight of box = 80 N

[tex]\mu_k[/tex] = Coefficient of kinetic friction = 0.25

[tex]\mu_s[/tex] = Coefficient of static friction = 0.5

F = Pulling force = 25 N

Static friction

[tex]f_s=\mu_s w\\\Rightarrow f_s=0.5\times 80=40\ \text{N}[/tex]

[tex]F<f_s[/tex]

The force of pulling is less than the static frictional force so this makes the friction force equal to the force of pulling.

So, the friction force on the box is 25 N.

Jennifer hits a stationary 0.04-kg ball, and it leaves her racket at 41.3 m/s. Time-lapse photography shows that the ball was in contact with the racket for 26.5 ms. What average force, in N, did the ball exert on the racket?

Answers

Answer:

  62.33N

Explanation:

We know that the relationship for the impulse and momentum is given as

Ft=mv

given data

mass m=0.04kg

t= 26.5ms= 26.5/1000= 0.0265seconds

velocity v= 41.3m/s

substituting in the expression we have

Ft=mv

make F subject of formula we have

F=mv/t

F=(0.04*41.3)/0.0265

F=1.652/0.0265

F=62.33N

Which statement is true about an object that is traveling in uniform circular motion?

Answers

The net force of the object is directed toward the center of the circular path

Part A What electron current is driven through a 2.3-mm-diameter iron wire by a 0.062 V/m electric field?

Answers

We know, Current is given by :

[tex]I = \dfrac{EA}{\rho}[/tex]

Here, [tex]\rho[/tex] is resistivity and for iron.

[tex]\rho=9.71\times 10^{-8}\ \Omega\ m[/tex]

Putting [tex]\rho[/tex] in above equation, we get :

[tex]I = \dfrac{0.062\times \pi\times (2.3\times 10^{-3})^2}{4\times 9.71\times 10^{-8}}[/tex]

[tex]I=2.65\ A[/tex]

Therefore, the electron current is 2.65 A.

Hence, this is the required solution.

A ball is thrown up in the air with an initial velocity of 40m/s what is the balls velocity after 2 seconds?

Answers

Answer:

20 m/s

Explanation:

velocity after 2 sec.  

v=40+(−10)t

=40−10∗2=20m/s

We have that for the Question "A ball is thrown up in the air with an initial velocity of 40m/s what is the balls velocity after 2 seconds?" it can be said that the balls velocity after 2 seconds

v=67.44m/s

From the question we are told

A ball is thrown up in the air with an initial velocity of 40m/s what is the balls velocity after 2 seconds?

Generally the Newtons equation for the  Motion  is mathematically given as

[tex]v=u+at\\\\Therefore\\\\v=40+9.8*2.8\\\\v=67.44m/s\\\\[/tex]

Therefore

the balls velocity after 2 seconds

v=67.44m/s

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i. What is the gravitational potential energy added to the steel beam when the beam reaches a height of 18.4 m? (1 point)

Answers

Answer:

59,566.32Joules

Explanation:

The question is incomplete. Here is the complete question.

At a construction site, a crane lifts a steel beam with a mass of 330 kg.

i. What is the gravitational potential energy added to the steel beam when the beam reaches a height of 18.4 m? (1 point)

Gravitational potential energy GPE = mgh

m is the mass of the steel beam = 330kg

g is the acceleration due to gravity = 9.81m/s²

h is the height the beam reaches = 18.4m

Substitute

GPE = 330 * 9.81 * 18.4

GPE = 3237.3 * 18.4

GPE = 59,566.32Joules

Hence the gravitational potential energy is 59,566.32Joules

Answer:

The increase in gravitational potential energy is approximately 60,000 J.

Explanation:

GPE=mgh

m=330

g=9.8^2

h=18.4

GPE=330*9.81*18.4

GPE=59,566.32 J

Hope I could help! :)

Object A has a mass of 12 g and a density of 3 g/cm3. Object B has a mass of 12 g and a density of 5 g/cm3. Which object has a greater volume and by how much? (4 points)
Object A, by 2 6 cubic centimeters
Object A, by 1.6 cubic centimeters
Object B, by 2 6 cubic centimeters
Object B, by 1.6 cubic centimeters

Answers

Answer:

object B has a greater volume and by2 g/cm3

A car driver traveling on a linear segment of a level road at 60 miles per hour (mph) slows down to 40 miles per hour in a road construction zone. If the car traveled a distance of 360 ft from the original speed to the final speed then what is the car deceleration rate in ft per sec2

Answers

Answer:

a=5.98 ft/sec

Explanation:

given

initial velocity u=60mph to ft per sec= 88ft/s

final velocity v=40 mph to ft per sec= 58.6 ft/s

distance s=360ft

convert feet to mile 360ft is 0.06miles

we can apply the expression

v^2=u^2-2as

58.6^2=88^2-2*a*360

3433.96=7744-720a

3433.96-7744=-720a

-4310.04=-720a

a=4310.04/720

a=5.98 ft/sec

Consider the situation a book a sliding to a stop while moving across the classroom floor. Of the forces listed identify which act upon the book

Answers

There aren’t any listed but friction and gravity are constant acting forces

The forces which act upon the book are Normal, Gravity, Air resistance, and Friction. Therefore, the (A), (B), (D), and (E) options are correct.

What are Normal force, Gravity, Air resistance, and Friction?

The normal force is a contact force that surfaces exert to prevent objects from passing through each other. If two surfaces are not in direct contact, they are able to exert a normal force on each other. The book and the floor are exerting normal on each other.

Gravity is the force by which the earth draws objects toward its center. The force of gravity keeps everything on the surface of the earth. Therefore, the sliding book on the floor experiences the force of gravity.

Air resistance is a force that arises due to air. The force acts in the opposite direction to the motion of an object through the air. As the book slides across the floor, it experiences resistance due to air.

Friction is the resistance caused by the surfaces that are in contact when they slide over each other. Friction arises due to the irregularities on the two surfaces. The book and floor both have irregularities on their surfaces which is caused friction between them.

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Your question is incomplete, but most probably the complete question was,

Consider the situation a book a sliding to a stop while moving across the classroom floor. Of the forces listed identify which act upon the book:

A)Normal,

B) Gravity

C)Applied

D) Air resistance,

E) Friction

F) Tension

Two masses, m_1m ​1 ​​ = 3.75 kg and m_2m ​2 ​​ = 6.34 kg, are connect by a string of negligible mass. The string passes over a frictionless pulley so that m_1m ​1 ​​ and m_2m ​2 ​​ hang down on opposite sides of the pulley. The whole system is released from rest. Calculate the tension in the string as the masses are moving.

Answers

Answer:

Explanation:

For the mass m1;

The sum of forces acting on the body is expressed according to Newton's second law as;

\sum Fx = m1ax

T - Ff = m1a .... 1

T is the tension

Ff is the frictional force acting on m1

For the mass m2:

\sumFy = m2a

W - T = m2a

m2g - T = m2a.... 2

W is the weight

g is the acceleration due to gravity

If the acceleration of the system is 0, the equation becomes;

From 2:

m2g - T = m2a.... 2

a = m2g-T/m2

From 1:

a = T-Ff/m1

Equate both accelerations

m2g-T/m2 = T-Ff/m1

Cross multiply

m1m2g - Tm1 = m2T-m2Ff

m1m2g+m2Ff = m2T+m1T

m1m2g+m2Ff = T(m2+m1)

T = m1m2g+m2Ff/m2+m1

Hence the tension in strings is expressed as

T = m1m2g+m2Ff/m2+m1

How does the temperature affect the amount of weathering

Answers

Temperature changes can also contribute to mechanical weathering in a process called thermal stress. Changes in temperature cause rock to expand (with heat) and contract (with cold). As this happens over and over again, the structure of the rock weakens

The fastest recorded pitch in major league baseball, thrown by Aroldis Chapman in 2010, was clocked at 169.1km/hr. If a pitch were thrown horizontally with this velocity, how far would the ball fall vertically (in meters) by the time it reached the home plate, 18.3m away?

Answers

Answer:

The ball would fall vertically for 112.45m

Explanation:

The vertical height of a horizontal throw is affected only by the speed of the throw and the acceleration due to gravity.

At this point, we may use this formula to determine the vertical height of the throw

vertical height = [tex]-v^2/2g[/tex]

The initial throwing speed has to be converted to m/s to ensure uniformity during the calculations. To do this we multiply by 1000 and divide by 3600

169.1km/hr = 46.972m/s

Maximum height = [tex]46.972^2 /2 \times 9.81=112.45[/tex] m

The pitch would make the ball fall vertically for 112.45m by the time it reached the home plate 18.2 m away

what is hubbles law? please put in simple terms

Answers

Answer:

the law that the velocity of recession of distant galaxies from our own is proportional to their distance from us.

Explanation:

Hubble's law, also known as the Hubble–Lemaître law, is the observation in physical cosmology that galaxies are moving away from the Earth at speeds proportional to their distance. In other words, the farther they are the faster they are moving away from Earth.

A hungry rabbit sprints... what is the average velocity of the rabbit between the times t = 2 s and t = 12 s

Answers

Answer: -0.10m/s

Explanation:

khan academy

A soccer player kicks a 0.5 kg ball and accelerates it at 50 m/s2. What force does the player apply to the ball?

Answers

Answer:

The answer is 25 N

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 0.5 × 50

We have the final answer as

25 N

Hope this helps you

Large igneous provinces are formed by ____________________, which can flow tens to hundreds of kilometers.

Answers

Answer:

Large igneous provinces are formed by flood basalt, which can flow tens to hundreds of kilometers.

Explanation:

What is the difference between fast-twitch and slow-twitch muscle fibers?
A. They are almost identical.
B. Fast-twitch fibers can deliver a quick burst of power. Slow-twitch
fibers can maintain a contraction for a longer time.
C. Fast-twitch fibers are what keep us going on a long bike ride or
hike. Slow-twitch fibers are what we use while dashing for the bus
or jumping up for a rebound.
D. Fast-twitch fibers take a long time to warm up, but are stronger
than slow-twitch fibers once they get going.

Answers

Answer:

B. fast-twitch fibers can deliver a quick burst of power. Slow-twitch fibers can maintain a contraction for a longer time.

Answer:

the person above is right, just came for answers lol :')

Explanation:

When a velocity vs time graph is slowed downwards, is the object still moving forward? Explain why or why not.

Answers

Answer:

Since velocity is considered a vector quantity and vectors show you in what direction it goes the object wont be moving forward but backwards because its a negative and negatives go to the left and that would be considered backwards.

Explanation:

Hope this helps

In the amusement park ride known as Magic Mountain Superman, powerful magnets accelerate a car and its riders from rest to 45 m/s (around 100 mi/h) in a time of 6.8 s. The mass of the car and riders is 5100 kg. Find the average net force exerted on the car and riders by the magnets.

Answers

Answer:

The average net force exerted on the car and riders by the magnets is 33751.8 newtons.

Explanation:

Let assume that car and its riders accelerate at constant rate, such that acceleration ([tex]a[/tex]), measured in meters per square second, can be found by using the following kinematic equation:

[tex]a = \frac{v_{f}-v_{o}}{t}[/tex] (Eq. 1)

Where:

[tex]v_{o}[/tex], [tex]v_{f}[/tex] - Initial and final speeds of the car and its riders, measured in meters per second.

[tex]t[/tex] - Acceleration time, measured in seconds.

If we know that [tex]v_{o} = 0\,\frac{m}{s}[/tex], [tex]v_{f} = 45\,\frac{m}{s}[/tex] and [tex]t = 6.8\,s[/tex], the average acceleration of the car is:

[tex]a = \frac{45\,\frac{m}{s}-0\,\frac{m}{s}}{6.8\,s}[/tex]

[tex]a = 6.618\,\frac{m}{s^{2}}[/tex]

By the Second Newton's Law, we find that average force exerted on the car and riders by the magnets ([tex]F[/tex]), measured in newtons, is:

[tex]F = m\cdot a[/tex] (Eq. 2)

Where [tex]m[/tex] is the mass of the car-riders system, measured in kilograms.

If we know that [tex]m = 5100\,kg[/tex] and [tex]a = 6.618\,\frac{m}{s^{2}}[/tex], the net force exerted on the car and riders is:

[tex]F = (5100\,kg)\cdot \left(6.618\,\frac{m}{s^{2}} \right)[/tex]

[tex]F = 33751.8\,N[/tex]

The average net force exerted on the car and riders by the magnets is 33751.8 newtons.

A playground merry-go-round has a radius R and a rotational inertia I. When the merry-go-round is at rest, a child with mass m runs with speed v along a line tangent to the rim and jumps on. The angular velocity of the merry-go-round is then:

Answers

Answer:

The angular velocity of the merry-go-round is [tex]\omega = \frac{m_{C}\cdot v}{R\cdot (I+m_{C}\cdot R^{2})}[/tex].

Explanation:

After a careful reading of the statement, we notice that merry-go-round-child system is a system with no external force exerting on it, such that the Principle of Angular Momentum Conservation can applied to analyze the system:

[tex]m_{C}\cdot \left(\frac{v}{R} \right) = (I+m_{C}\cdot R^{2})\cdot \omega[/tex] (Eq. 1)

Where:

[tex]m_{C}[/tex] - Mass of the child, measured in kilograms.

[tex]v[/tex] - Initial speed of the child, measured in meters per second.

[tex]R[/tex] - Radius of the playground merry-go-round, measured in meters.

[tex]I[/tex] - Moment of inertia, measured in kilograms per square meter.

[tex]\omega[/tex] - Angular velocity of the merry-go-round-child system, measured in radians per second.

Then, we clear the final angular speed:

[tex]\omega = \frac{m_{C}\cdot v}{R\cdot (I+m_{C}\cdot R^{2})}[/tex]

The angular velocity of the merry-go-round is [tex]\omega = \frac{m_{C}\cdot v}{R\cdot (I+m_{C}\cdot R^{2})}[/tex].

A car traveling 14 m/s accelerates at a rate of 0.95 m/s2 for an interval of 8 s. What is the final
velocity of the car? Remember: Diagram, Knowns, Equation, Rearrange, Solve.

Answers

using v = u + at
v = 14 + (0.95x8) = 14 + 7.6 = 21.6 m/s

Suppose a small compact car with a mass of 1000 kg is traveling north on Morewood Avenue at a speed of 15 m/s. At the intersection of Morewood and Fifth Avenues, it collides with a truck with a mass of 2000 kg that is traveling east on Fifth Avenue at 10 m/s. Treating each vehicle as a particle, find the total momentum (magnitude and direction) just before the collision.

Answers

Explanation:

We are expected to solve for the total momentum before collision

the expression for momentum is given as

p = mv

p =momentum

m=mass

v=velocity

For small compact truck

m1=1000kg

v1=15m/s

For small truck

m1=2000kg

v1=10m/s

the total momentum can also be expressed as

Ptotal=m1v1+m2v2

Ptotal=1000*15+2000*10

Ptotal=15000+20000

Ptotal=35000kg•m/s

The direction is east because the momentum of the truck is more than the car

Other Questions
Write each phrase using the LONG possessive adjective, help i dont know lol :) im hungry tho 332/10 as an mixed number Complete the sentence: When you write a ___________, you should cover the most important points, not every detail. Help me plz :((((( helpsssbme tyyy These are normal memories that you're currently not thinking about. To go with the question i just asked PLEASE HELP FAST CORRECT ANSWERS ONLYRecall that there are two kinds of life changes: social change and personal change. An example of a personal change might be moving to a new town. An example of a social change might be how many people have moved from using landline telephones to using mobile phones.In the space provided, describe some of the changes going on in your life right now. Brainstorm your ideas and write them down. Remember, while brainstorming you dont have to worry about organization or grammar. Brainstorming includes freewriting, cluster maps, and even a bulleted list of ideas. Make sure that you include both personal changes and social changes.In terms of social changes, your response might include some of the following:What changes in technology have occurred recently?Are there other changes happening in society that you can think of?How have those changes affected you? Are they positive or negative changes?In terms of personal changes, your response might include some of the following:What has happened in your life recently?Have you learned any new skills or concepts?Have you had any new experiences?Did you make any new friends?How have those changes affected you? Are they positive or negative changes? Shays Rebellion reflected which of the following tensions in United States society during the 1780s? Which expression is equivalent to 24 - (-6) HELP ASAP! How did anne feal after her father wrote her a letter back? how did it change her? what is the change in total profit of cleaning the fifth driveway if the price Mr. Plow can charge is $10 per driveway Tessa heard that a hacker recently broke into her friends e-mail account. Tessa uses her home computer to manage her personal business and wants to make sure her information and online accounts are protected from hackers. What steps should Tessa take to protect her accounts? Check all that apply.change passwords frequentlyreview privacy settingschange current screen namepurchase another computeradjust safety settings Chang is putting money into a savings account. He starts with $450 in the savings account, and each week he adds $60. Let S represent the total amount of money in the savings account (in dollars), and let W represent the number of weeks Chang has been adding money. Write an equation relating S to W. Then use this equation to find the total amount of money in the savings account after 13 weeks. Fill in the blank with the correct number.The number ________ is divisible by 2, 3, 4, 6, and 10. A. 44 B. 180 C. 280 D. 385 4.) Cellular phone company A has 86,000,000 customers and cellular phone company B has83,200,000 customers. How many more customers does cellular phone company A have thancellular phone company B? Express your answer in standard form and scientific notation. describe the graph below linear or nonlinear Question #4A person dealing with mental health issues can have a stigmaagainst themselves and others dealing with behavioral health.n# 1n#2n #3n#4TrueO FalseU Differences arose on how to count enslaved people for representation in the ________.1. House of representatives or 2. SenatePLEASE ANSWER NOW!!!! Book sales on the Internet (in billions of dollars) in year x are approximated by f(x) = 1.84 +2.1. In x, where x = 0 corresponds to 2000. How much will be spent on Internet book sales in 2008? Round to the nearest tenth.a. 6.2 billion b. 8.0 billion c. 3.9 billion d. 6.7 billion