How high will a 1-kilogram ball go if it is thrown straight up into the air with an initial velocity of 30 m/sec?

Answers

Answer 1

h max = 45.92 m

Further explanation

Given

1 kg ball

vo=initial velocity = 30 m/s

Required

Height

Solution

We can use the principle of energy conservation or parabolic motion

For parabolic motion

h max = vo²sin²θ/2g(θ= 90° for straight up)

For conservation energy :

KE₁=PE₂

1/2.m.vo² = m.g.h

We choose parabolic motion

h max = vo²sin²θ/2g

h max = 30²sin²90/2 x 9.8

h max = 45.92 m


Related Questions

According to Coulomb's Law, if the distance between two charged particles is doubled, the electric force will be _________. *

Answers

Answer: reduced by 1/4

Explanation:

The force will be reduced by 1/4. Try plugging in 2r, then squaring it. You will get 4r^2, which is essentially dividing the force by 4

Which object exerts the action force?
Which object exerts the reaction force?
In what direction does the action force push?
In what direction does the reaction force push?

Answers

For answering this question,let us assume that a person is pushing against the walls,so now:

Which object exerts the action force?

Person

Which object exerts the reaction force?

Wall

In what direction does the action force push?

Backward

In what direction does the reaction force push?

Forward

The answer varies from different scenarios.

Answer:

diver, diving board, down, and up.

Explanation:

Marquette King, formerly of the Denver Broncos, is practicingkicking off using a kicking holder with the ball on the ground.For one of the kicks the ball reaches a height of 90.6 m andlands on the ground 53 yds (48.5 m) away. Find the magnitudeof the initial velocity given by his kick to the ball. Treat airresistance as negligible. Hint: Even though the horizontal andvertical motions are independent, there is a quantity that iscommon to both of them.

Answers

Answer:

Explanation:

Maximum height reached = 90.6 m . Range = 48.5 m

. Let u be the initial velocity at angle α .

Horizontal range is covered by horizontal component of u .

Vertical height is achieved by vertical component

v² = u² sin² α - 2gh , t is time taken to attain maximum height .

0 = u² sin² α - 2 x 90.6 x 9.8  

u² sin² α = 2 x 887.88  -------( 1 )

Range R = u² sin2α / g

48.5 = 2 u² sinα . cos α / 9.8

u² sinα . cos α = 237.65 -----------------------------  ( 2 )

( 1 ) / ( 2 )

Tan α = 2 x 887.88 / 237.65 = 7.47

α = 82⁰

u² sin² α = 2 x 887.88

u² sin² 82 = 2 x 887.88

u² = 1812

u = 42.56  m /s

Bryce, a mouse lover, keeps his four pet mice in a roomy cage, where they spend much of their spare time, when they're not sleeping or eating, joyfully scampering about on the cage's floor. Bryce tracks his mice's health diligently and just now recorded their masses as 0.02130.0213 kg, 0.01650.0165 kg, 0.01850.0185 kg, and 0.01930.0193 kg. At this very instant, the x‑x‑ and y‑y‑ components of the mice's velocities are, respectively, (0.675 m/s,−0.417 m/s)(0.675 m/s,−0.417 m/s) , (−0.249 m/s,−0.809 m/s)(−0.249 m/s,−0.809 m/s) , (0.395 m/s,0.953 m/s)(0.395 m/s,0.953 m/s) , and (−0.207 m/s,0.227 m/s)(−0.207 m/s,0.227 m/s) . Calculate the x‑x‑ and y‑y‑ components of Bryce's mice's total momentum, pxpx and pypy .

Answers

Answer: [tex]p_{x}=[/tex] 0.0135814 kg.m/s

              [tex]p_{y}=-0.000219[/tex] kg.m/s

Explanation: When an object with mass is in motion, we say the object has momentum (p). Momentum is dependent on mass and velocity:

p = m.v

The total momentum of Bryce's mice is calculated as

x-axis

[tex]p_{x}=\Sigma m.v_{x}[/tex]

[tex]p_{x}=[(0.0213)(0.675)+(0.0165)(-0.249)+(0.0185)(0.395)+(0.0193)(-0.207)][/tex]

[tex]p_{x}=[/tex] 0.0135814

At the x-axis, total momentum of Bryce's mice is 0.0135814 kg.m/s.

y-axis

[tex]p_{y}=\Sigma m.v_{y}[/tex]

[tex]p_{y}=[(0.0213)(-0.417)+(0.0165)(-0.809)+(0.0185)(0.953)+(0.0193)(0.227)][/tex]

[tex]p_{y}=-0.000219[/tex]

At the y-axis, total momentum of Bryce's mice is -0.000219 kg.m/s.

Predictions about the future based on the position of planets is an example of
- physics
- biology
- earth science
- pseudoscience

Answers

Answer:

astronomi

Explanation:

sciemce ya ya

Match to the correct answers
A:You measure power in
B:Coal is a power source that is
C:Solar is a power source that is
D:You measure work done in
E:Fuels that took millions of years to form are
Renewable
watts
non-renewable
fossils fuels
joules
plsss help me

Answers

A. You measure power on watts.
B. Non-renewable
C.renewable
D. Joules
E. Fossil fuels

A plastic rod 1.6 m long is rubbed all over with wool, and acquires a charge of -9e-08 coulombs. We choose the center of the rod to be the origin of our coordinate system, with the x-axis extending to the right, the y-axis extending up, and the z-axis out of the page. In order to calculate the electric field at location A = < 0.7, 0, 0 > m, we divide the rod into 8 pieces, and approximate each piece as a point charge located at the center of the piece.

Answers

Solution :

Length of the plastic rod , L = 1.6 m

Total charge on the plastic rod , Q = [tex]$-9 \times 10^{-8}$[/tex] C

The rod is divided into 8 pieces.

a). The length of the 8 pieces is , [tex]$l=\frac{L}{8}$[/tex]

                                                         [tex]$=\frac{1.6}{8}$[/tex]

                                                         = 0.2 m

b). Location of the center of the piece number 5 is given as : 0 m, -0.09375 m, 0 m.

c). The charge q on the piece number 5 is given as

[tex]$q=\frac{Q}{L}\times l$[/tex]

[tex]$q=\frac{-9 \times 10^{-8}}{1.6}\times0.2$[/tex]

 = [tex]$-1.125 \times 10^{-8}$[/tex] C

d). WE approximate that piece 5 as a point charge and we need to find out the field at point A(0.7 m, 0, 0) only due to the charge.

We know,  the Coulombs force constant, k = [tex]$8.99 \times 10^9 \ N.m^2/C^2$[/tex]

So the X component of the electric field at the point A  is given as

[tex]$E_x = 8.99 \times 10^9 \times 1 \times 10^{-8} \ \cos \frac{187.628}{0.70625}$[/tex]

     = -126.15 N/C

The Y component of the electric field at the point A is

[tex]$E_y = 8.99 \times 10^9 \times 1 \times 10^{-8} \ \sin \frac{187.628}{0.70625}$[/tex]

    = -16.93 N/C

Now since the rod and the point A is in the x - y plane, the z component of the field at point A due to the piece 5 will be zero.

∴ [tex]$E_z=0$[/tex]

Thus, [tex]$E= <-126.15,-16.93,0>$[/tex]

Imagine that I have a ping-pong ball and a bowling ball resting on the floor of our classroom. I go up to the bowling ball and give it a push so that it starts rolling. If I give a push of the exact same strength to the ping-pong ball, how will the resulting motion of the ping-pong ball be different

Answers

Answer:

the speed and aceleration of the ping pong ball is greater than that of the bowling ball.

Explanation:

We can analyze this exercise from several points of view, if we use Newton's second law

Bowling ball

           F = M a₁

pingpongg ball

           F = m a₂

as the forces the same

          M a₁ = m a₂

          a₂ = [tex]\frac{M}{m}[/tex] a₁

Since the mass of the bowling ball is much greater than the ping pong ball,

          a₂ »a₁

so the acceleration of the ping pong ball is much greater than the acceleration of the bowling ball.

If we use the relationship of momentum and momentum, assuming that the time for the two cases is the same and that both start from rest

Bowling ball

           I = F t = Δp

           I = M (v₁ - v₀)

Ping pong ball

           I = F t = Δp

           I = m (v₂ -v₀)

the impulse itself

          M v₁ = m v₂

          v₂ = [tex]\frac{M }{ m}[/tex] v₁

so we conclude that the speed of the ping pong ball is much greater than the speed of the bowling ball.

In conclusion the speed and aceleration of the ping pong ball is greater than that of the bowling ball.

REAL ANSWER OR REPORTED, REAL GETS BRAINLIST
2. What is the weight of:
A 32 kg child
An 82 kg linebacker
A 1000 kg car


3. What is the mass of:
A student who weighs 524 Newtons
A table that weighs 441 Newtons
A hammer that weighs 51 Newtons

4. A 15 kg box sits motionless on the floor.
Draw a force diagram for the box.
Write a vertical Fnet equation for the box.
Determine the weight of the box.
What is the magnitude of the normal force?

Answers

Answer:

32kg = 313.6N

82kg = 803.6N

1000kg = 9800N

524N = 53.47kg

441N = 45kg

51N = 5.20kg

for the box diagram the weight of the 15kg box is 147N

the net force will be equal to zero because the box is motionless

Fg goes downward arrow of box 147N

Fnorm goes upward arrow of box 147N

Mary spots Bill approaching the dorm at a constant rate of 2.00 m/s on the walkway that passes directly beneath Mary's window, 17.0 m above the ground. When Bill is L = 130 m away from the point below Mary's window she decides to drop an apple down to him. Ignore the effects of air resistance in your calculations.

Required:
How long should Mary wait to drop the apple if Bill is to catch it 1.65 m above the ground?

Answers

Answer:

Mary will have to wait for 63.2 seconds

Explanation:

Time required for the apple to drop from a height of 17.0 m above the ground to 1.65 m above the ground is given by the formula below:

t = √2h/g  where h is height through which the object falls, g is acceleration due to gravity

h = 17.0 - 1.65 = 15.35 m

g = 9.8 m/s²

t = √(2 * 15.35/9.8)

t = 1.77 s or approximately 1.8 s

Time taken for bill to get to the point below Mary's window is given below;

time taken = distance/velocity

distance = 130 m; velocity = 2.0 m/s

time taken by Bill = 130/2.0 = 65 s

Therefore, Mary will have to wait for (65 - 1.8) s = 63.2 seconds

Mary should have to wait for 63.2 seconds

Calculation:

t = √2h/g

here h is height via which the object falls,

g represent acceleration due to gravity

So,

h = 17.0 - 1.65

= 15.35 m

And,

g = 9.8 m/s²

Now

t = √(2 * 15.35/9.8)

t = 1.77 s or approximately 1.8 s

Now the time taken should be

= 130/2.0

= 65 s

So,

= (65 - 1.8) s

= 63.2 seconds

learn more about the time here: https://brainly.com/question/2911365

Look at the equation. What detail is missing? 3 m/s2= (33 m/s - X)/30 S

Answers

Answer:

The starting velocity.

Explanation:

We must understand that this equation comes from the following equation of kinematics.

[tex]v_{f}=v_{o}+a*t[/tex]

where:

Vf = final velocity = 33 [m/s]

Vo = starting velocity [m/s]

a = acceleration = 3 [m/s²]

t = time = 30 [s]

So, these values can be assembly in the following way:

[tex]v_{f}=v_{o}+a*t\\a*t=v_{f}-v_{o}\\3=\frac{33-v_{o}}{30}[/tex]

Glucose is the main source of energy.
True or false

Answers

Answer:

True :p

Explanation:

Carbohydrates are foods that get converted into glucose.

What is a watt a unit of?

light


time


distance


power

Answers

Answer:

power...............m....

Answer:

The dimension of power is energy divided by time. In the International System of Units (SI), the unit of power is the watt (W), which is equal to one joule per second.

SI unit: watt (W)

In SI base units: kg⋅m2⋅s−3

Explanation:

A negatively-charged rod is brought close to (but does not touch) two neutral spheres that are in contact with each other but insulated from the ground. If the two spheres are then separated, what kind of charge will be on the spheres

Answers

Answer:

One sphere obtains a positive charge, while the other obtains a negative charge.

Explanation:

When the negatively-charged rod is brought close to the two neutral spheres in contact with each other, the electrons in both spheres are repelled away from the rod and thus those electrons move into the second sphere farther away from the rod.

The first sphere is now short of electrons.

When the spheres are separated, the first sphere which is short of electrons now carries a net positive charge, while the other sphere which has excess electrons now carries a net negative charge.

Choose the best explanation from among the following:_________.
1. Charge is conserved, and therefore the mass of the object will remain the same.
2. A positive charge increases an object's mass; a negative charge decreases its mass.
3. To give the object a negative charge we must give it more electrons, and this will increase its mass.

Answers

Answer: 3. To give the object a negative charge we must give it more electrons, and this will increase its mass.

Explanation:

Suppose we have an object and we negatively charge it.

Then we are "adding" N electrons to the object.

Remember that the mass of an electron is:

m = 9.11*10^(-31) kg

Then if we add N electrons to an object of mass M, the new mass of the object will be:

Mass = M + N*9.11*10^(-31) kg

So we will have an (almost negligible) increase of the mass of the object.

(Something similar can happen if the object is positively charged, where we remove electrons, then the mass of the object decreases)

Then the correct option is:

3. To give the object a negative charge we must give it more electrons, and this will increase its mass.

A north magnetic pole is facing another north magnetic pole with a distance xx. If the distance between the poles becomes 12x12x, what happens to the magnitude of the field energy between them

Answers

Answer:

Explanation:

When two north magnetic poles are  placed close to each other , they will repel each other . If distance between them is increased due to mutual repulsion from x to 12 x , work is done by the magnetic field . This results in decrease of magnetic field energy .

Hence , when the distance between the poles becomes 12x from x , the magnitude of the field energy between them decreases .

Which of the following statements is FALSE regarding the law of conservation of energy?


The total amount of energy remains constant.


Energy can neither be created nor be destroyed.


Energy can be transformed from one form to another.


The total amount of energy changes upon an energy transformation.

Answers

Answer:

D

Explanation:

because it doesn't agree with the law of definite proportion

and energy can niether be created nor destroyed but can be transformed from one form to another

The false statement will be, The total amount of energy changes upon an energy transformation.

What is conservation of energy?

The conservation of energy according to the first law of thermodynamics is that energy neither be created nor be destroyed, but can be transformed from one form to another form.

Now we can take many examples like if we are running a bicycle our efforts are converted to the rotation of the wheel and the rotation energy is converted to the linear energy of our motion.

But the necessary point is that from the second law of thermodynamics it states that the energy can not be completely converted to the other form but some part of it is losses in the environment.

Thus the false statement will be, The total amount of energy changes upon an energy transformation.

To know more about laws of conservation of energy, follow

https://brainly.com/question/166559

What is the frequency of highly energetic ul-
traviolet radiation that has a wavelength of
124 nm?
The speed of light is 3 x 108 m/s.
Answer in units of Hz.

Answers

Frequency = (speed) / (wavelength)

Frequency = (3 x 10⁸ m/s) / (124 x 10⁻⁹ m)

Frequency = 2.42 x 10¹⁵ Hz

A cart was allowed to roll down a ramp from rest. It reached the bottom of the ramp with a speed of 25 cm/s. A student could conclude that the cart

Answers

Answer:

A student could conclude that the cart gained momentum as it rolled down.

Explanation:

If the cart was allowed to roll down the ramp from rest, it means that the initial velocity of the cart is zero (0). Also, if the final velocity of the cart became 25 cm/s, it means that the velocity of the cart increased from 0 to 25 cm/s.

Therefore, A student could conclude that the cart gained momentum as it rolled down.

1.A river flowing steadily at a rate of 240 m3/s is considered for hydroelectric power generation. It is determined that a dam can be built to collect water and release it from an elevation difference of 50 m to generate power. Determine how much power can be generated from this river water after the dam is filled

Answers

Answer:

the power that can be generated by the river is 117.6 MW

Explanation:

Given that;

Volume flow rate of river v = 240 m³/s

Height above the lake surface a h = 50 m

Amount of power can be generated from this river water after the dam is filled = ?

Now the collected water in the dam contains potential energy which is used for the power generation,

hence, total mechanical energy is due to potential energy alone.

[tex]E_{mech}[/tex] = m(gh)

first we determine the mass flow rate of the fluid m

m = p×v

where p is density ( 1000 kg/m³

so we substitute

m = 1000kg/m³ × 240 m³/s

m = 240000 kg/s

so we plug in our values into ( [tex]E_{mech}[/tex] = m(gh) kJ/kg )

[tex]E_{mech}[/tex] = 240000 × 9.8 × 50

[tex]E_{mech}[/tex] = 117600000 W

[tex]E_{mech}[/tex] = 117.6 MW

Therefore, the power that can be generated by the river is 117.6 MW

What are 3 things you could you do this week to help you connect better with kids in
your classes?

Answers

Answer:

In my physics class, something that helps connect better with kids is keeping connected with them always make sure to ask if they understand what you're teaching if they are following because sometimes most kids are to afraid to admit that they are lost, another way to connect with kids is maybe posting surveys to be able to check in with each student especially during this hard times :)

Explanation:

1. start with fun activities.

2. Encourage single-tasking.

3. Designate a learning playing field.

Using your knowledge on personal care products, how does sunscreen

lotion protect your skin from the damaging effect of ultraviolet rays?

Explain why of x-rays and gamma rays are commonly used in

radiotherapy.​

Answers

Answer:

Ultraviolet rays from sun are very harmful from skin and can cause sunburn and skin diseases especially ultraviolet B rays. A sunscreen  lotion act as a protection barrier on the skin that restrict the direct contact of UV rays with skin and filter the harmful rays to enter the skin.

Radiotherapy is a medical therapy use to treat cancer. Radiotherapy commonly uses x-rays and gamma rays because they are high-energy particles or waves that kills or destroys the cancer cells.

Sunscreen lotion is able to filter this damaging ultraviolet radiation and prevent it from damaging the skin.

The sun reaches us from outer space brings ultraviolet rays to us. Ultraviolet rays are known to have some damaging effects on the skin. One way to protect our skin from this damaging ultraviolet rays is to use sunscreen lotion which is able to filter this damaging ultraviolet radiation and prevent it from damaging the skin.

X-rays and gamma rays are used in radiotherapy because they are light energy rays which are able to penetrate and destroy malignant cells in the body.

Learn more: https://brainly.com/question/13695751

Connective Tissue in a tendon is

Answers


Overview. A tendon is a fibrous connective tissue which attaches muscle to bone. Tendons may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure.

A particle with a charge of -4.3 μC and a mass of 4.4 x 10-6 kg is released from rest at point A and accelerates toward point B, arriving there with a speed of 80 m/s. The only force acting on the particle is the electric force. What is the potential difference VB - VA between A and B? If VB is greater than VA, then give the answer as a positive number. If VB is less than VA, then give the answer as a negative number.

Answers

Answer:

ΔV = - 3274 V

Explanation:

For this exercise we can use conservation of energy

starting point.

         Em₀ = U = q ΔV

final point

          Em_f = K = ½ m v²

energy is conserved

          Em₀ = Em_f

          q ΔV = ½ m v²

          ΔV = [tex]\frac{m \ v^2 }{q}[/tex]

let's calculate

          ΔV = [tex]\frac{4.4 \ 10^{-6} \ 80^2 }{ 2 \ 4.3 10^{-6} }[/tex]

          ΔV = 3274.4 1 V

since the charge q is negative, the potential at point B must be less than the potential at point A, so the answers

          ΔV = - 3274 V

a body is projected at an angle of 30 degrees to the horizontal with a velocity of 15m/s, calculate the time it takes to reach the greatest height take g=10ms2 and neglect air resistance​

Answers

Explanation:

The vertical component the velocity of the projectile is 15 m/s x sin 30 = 7.5 m/s.

The body is accelarating downwards at 10 m/s^2.

This means that every second its upward velocity reduces by 10 m/s.

So if the body is travelling upwards at 7.5 m/s then how long does it take for the velocity to become 0?

(7.5 m/s) / (10 m/s^2) = 0.75 s

Why is cloning done before an investigation begins??

Answers

Answer:Purpose of Cloning

A forensic image of a hard drive captures everything on the hard drive, from the physical beginning to the physical end. ... Hard drives are susceptible to failure. Having two clones gives an investigator one to examine and one to fall back on.Therapeutic cloning involves creating a cloned embryo for the sole purpose of producing embryonic stem cells with the same DNA as the donor cell. These stem cells can be used in experiments aimed at understanding disease and developing new treatments for disease.

Explanation:

hope this helps have a nice night lo❤️❤️❤️l

Cloning

Cloning is defined as a technique used by scientists to make exact genetic copies of living things. Genes, cells, tissues, and even whole animals can all be cloned.

Purpose of Cloning

Everything on the hard drive is captured by the forensic image. Hard drives can be a failure. If possible, the original drive should be preserved in a safe place and only brought out to reimage if needed. Ideally, all examinations are done on a clone as opposed to the original.

One of the cloning types is Therapeutic cloning which involves creating a cloned embryo for the sole purpose of producing embryonic stem cells with the same DNA as the donor cell. These stem cells can be used in experiments aimed at understanding disease and developing new treatments for disease.

To know more about cloning, follow the link given below.

https://brainly.com/question/25737082.

ASAP please thank you !
Find O and P

Answers

Explanation:

O + 6V = 9V, so O = 3V

P = 9V as it is parallel to the 9V power supply.

What is an
example of a force?
Pressure
Power
Energy
Weight

Answers

Answer:

weight

Explanation:

weight is the pull of gravity so its a force !!

The amount of kinetic energy an object has depends on its mass and its speed.

a. True
b. False

Answers

Answer:

True

Explanation:

The kinetic energy of an object is the energy that it possesses due to its movement or motion.

True, the amount of kinetic energy an object has depends on its mass and its speed.

The kinetic energy of a moving object is directly proportional to the square of its velocity and directly proportional to its mass.

During their physics field trip to the amusement park, Leslie and Maria took a ride on the Whirligig. The Whirligig ride consists of long swings which spin in a circle at relatively high speeds. As part of their lab, Leslie and Maria estimate that the riders travel through a circle with a radius of 6.5 m and make one circle every 5.8 seconds. Determine the frequency, the period, the speed and acceleration of the riders on the Whirligig

Answers

Answer:

a) frequency = 0.1724 Hz

b) Period = 5.8 sec

c) speed = 7.04 m/s

d) acceleration = 7.62 m/s²

Explanation:

Given that;

radius = 6.5m

time period = 5.8 sec every circle

a)  the frequency

frequency is the number of rotation in unit time

frequency = 1 / time period = 1/5.8

frequency = 0.1724 Hz

b)  the period

period is time taken in one rotation

period = total time / rotation = 5.8 / 1

Period = 5.8 sec

c)  the speed

speed = distance/time = circumference/time period = 2πr / t = (2π×6.5) / 5.8

speed = 7.04 m/s

d) acceleration

To find the acceleration we take the linear velocity squared divided by the radius of the circle.

so

acceleration = v² / r = (7.04)² / 6.5 = 49.5616 / 6.5

acceleration = 7.62 m/s²

Other Questions
PLZ HELP!!! BRAINLIEST!!!Why did southern plantation owners support slavery?It cost less to buy slaves than to hire workers.Slaves did a better job harvesting cotton, sugar cane, and tobacco than anyone else.Slaves owned small parcels of land. Without them, the plantations would not be large enough to grow crops.Owners did most of the work on plantations. -8m 6(1 - 4m) = -102 is this section is about how plastic bags affect the environment a claim or not HAIRCUT Josiah went to the localbarber to get his hair cut. It cost$18 for the haircut. Josiah tippedthe barber 15%. What was the totalcost of the haircut including thetip? What is the solution? 1 pointIf the element Lithium (Li) were to bond with the element Sulfur (s), whattype of bond can you predict will be formed and why?*A. Covalent-Li and S are two nonmetalsB. Covalent-Li is a metal and S is a nonmetalC. Ionic-Li and S are two nonmetalsD. Ionic-Li is a metal and S is a nonmetal Rank the effective nuclear charge Z* experienced by a valence electron in each of these atoms: atom Z* experienced by a valence electron. An atom of carbon. An atom of fluorine. An atom of beryllium. An atom of boron. find the unknown side length x right here answer in simplest radical formA.241B.429C.48D.58 Determine the simple interest when: principal: $890, interest rate: 4.25%, time: 2 year The scene where Simon meets the "Lord of the Flies" is probably the most famous scene in the book, and that's why we have only one question today, so that we can focus on it. What similarities can you find between this scene and the biblical story of Jesus' temptation in the desert? What predictions can you make for the rest of the book as a result of this scene? ? QuestionDrag the tiles to the correct boxes to complete the pairs.Match the types of lines to what they signify.TilesSmooth linesBlurred linesThick linesPairsboldnesscalmnessuneasematch the types of lines to what they signify A DVD originally costs $16. The discounted price is $12. What is thepercent change?25% increase25% decrease18.75% increase 18.75% decrease Which one of those answers?And explain? 4*9x4*3 whats the answer A computer that cost 1099 last year costs 999 this year. What is the percent of change in price rounded to the nearest tenth? ? Type your response in the box.Read the following excerpt from a science fiction story:The man pressed his hand against the biological key-reader that locked the computer room. After touching his hand against the coldsurface, the large metal door groaned and rumbled up into the ceiling. The man walked through the opening. His entrance triggeredthe lights in the room to come alive. In the back of the large, hollow room, he heard a machine power up, Its electric board Inhaling andsighing as the current pulsed through the metallic cavern.What is one figurative device the writer uses to amplify the sense of advanced technology, and what is the effect of this device? Type the correct answer in each blank. Use numerals instead of words. If necessary, use / for the fraction bar(s).Charlie runs a book rental business. He currently charges $3 per book and rents out an average of 38 books a day.According to a study, for every 50 increase in rental price, the average business can expect to lose 4 rentals a day.Complete the equation that models this scenario, where b(x) is the revenue generated and x is the number of 50 price increases.b(x) = -____x2 + ____x + _____ which is largest 4.12 or 4.21 Let's tour around East Asia!Directions: Name each picture according to the country they belong. Write either it's from CHINA,JAPAN, or KOREA. ..I gave brainlest.. right answer!! neeed help in math pleaseee