A man walks 30 m to the west, then 5 m to the east in 45 seconds.
What is his average speed?

Answers

Answer 1
The displacement is the distance from the beginning point to the ending point. The time was just to throw you off. If he walks 30m due west, and then 5m due east, his displacement would be 30-5=25m to the west.

Related Questions

Somebody, please help me with these by April 6 I'm about to fail my class

1. Describe specific heat capacity and its use in calorimetry.
2. Define latent heat and how it is different than specific heat capacity.
3. Describe how a phase diagram changes when changing from a solid to a liquid.
4. Describe how work is done is related to a change in the volume of a fluid.
—Continue on the next page—
5. What is the relationship of change in internal energy, work, and heat? Explain the significance in terms of energy.
6. As succinctly as possible, explain why it is impossible to have an engine that is 100% efficient.
7. Describe the application of Archimedes principle in everyday terms.
Practice
8. 50 grams of a substance increases its temperature by 10 degrees when 100 J of heat is added. What is the specific heat capacity of the substance?
9. Ten kilograms of a substance has a latent heat of 1000 J/kg. How much energy does it take to change the phase of this substance?
—Continue on the next page—

10. The work done by a piston is measured to be 1000 J. If the pressure is a constant 1000 Pa, what is the change in volume of the piston?
11. Is the process described in #10 isovolumetric? Explain.
12. Is it possible for a substance to change the temperature in an isovolumetric and adiabatic process? Explain.
13. A substance is heated with 1000 J and does 700 J of work on the atmosphere. What is the change in the internal energy of the substance?
14. An engine causes a car to move 10 meters with a force of 100 N. The engine produces 10,000 J of energy. What is the efficiency of this engine?
—Continue on the next page—

15. If a ball of radius 0.1 m is suspended in water, density = 997 kg/m^3, what is the volume of water displaced and the buoyant force?
16. A 10 kg ball of volume = 0.005 m3 is set on a lake. Describe what will happen to the ball.
Application
A group of physics students heats a vial of water, which has a balloon at the top that traps the water vapor and air.
17. Describe how much the internal energy is changed if the students are adding heat to the water via a Bunsen burner. No need to calculate anything.
18. If 50 grams of water start to boil, then how much heat must be added to completely boil off the water? The latent heat of vaporization is 2,260,000 J/kg
—Continue on the next page—

19. Assume this process is 10% efficient, how much work is done by the gas expanding into the atmosphere?
20. Assuming the atmospheric pressure to be constant at 101,325 Pa, by what amount does the volume of the balloon change?

Answers

Answer:

im sorry i would help but thats too much

1- charging by touch occurs when electrons are transmitted by direct contact.
(Right)
(wrong)

2- Electric charges are preserved, they are not created or destroyed.
(Right)
(wrong)​

Answers

Answer:

#1 - True (touch) charging when electric conductors actually touch one another.

#2. True - electrical charges are conserved (not destroyed)

Two identical copper blocks are connected by a weightless, unstretchable cord through a frictionless pulley at the top of a thin wedge. One edge of the wedge is vertical, and the tip makes an angle of 33. The block that hangs vertically weighs 2.85 kg, and the block on the incline weighs 2.94 kg. If the two blocks do not move, what is magnitude of the force of friction on the second second block

Answers

Answer:

13.6 N

Explanation:

Since one side of the wedge is vertical and the wedge makes and angle of 33 with the horizontal, the angle between the weight of the copper block on the incline and the incline is thus 90 - 33 = 57.

Let M be the mass of the block that hangs, m be the mass of the block on the incline and T be the tension in the weightless unstretchable cord.

We assume the motion is downwards in the direction of the hanging block, M.

We now write equations of motion for each block.

So

Mg - T = Ma    (1) and T - mgcos57 - F = ma where F is the frictional force on the block on the incline and a is their acceleration.

Now, since both blocks do not move, a = 0.

So, Mg - T = M(0) = 0     and T - mgcos57 - F = m(0) = 0

Mg - T = 0    (3) and T - mgcos57 - F = 0 (4)

From (3), T = Mg

Substituting T into (4), we have

T - mgcos57 - F = 0

Mg - mgcos57 - F = 0

So, Mg - mgcos57 = F  

F = Mg - mgcos57

F = (M - mcos57)g

Since g = acceleration due to gravity = 9.8 m/s², and M = 2.94 kg and m = 2.85 kg.

We find F, thus

F = (2.94 kg - 2.85 kgcos57)9.8 m/s²

F = (2.94 kg - 2.85 kg × 0.5446)9.8 m/s²

F = (2.94 kg - 1.552 kg)9.8 m/s²

F = (1.388 kg)9.8 m/s²

F = 13.6024 kgm/s²

F ≅ 13.6 N

The moment of inertia of the club head is a design consideration for a driver in golf. A larger moment of inertia about the vertical axis parallel to the club face provides more resistance to twisting of the club face for off-center hits. The mass of one club head is 200 g and its moment of inertia is 5000 g cm2 . What is the radius of gyration of this club head

Answers

Answer:

Explanation:

Moment of inertia I = M k² , where M is mass and k is radius of gyration .

Putting the given values in the equation

5000 = 200 x k²

k² = 25

k = 5 cm .

Radius of gyration is 5 cm .

A loop of wire carrying a current of 2.0 A is in the shape of a right triangle with two equal sides, each 15 cm long. A 0.7 T uniform magnetic field is parallel to the hypotenuse. The total magnetic force on the two equal sides has a magnitude of:Group of answer choices0.30 N0 N0.51 N0.41 N

Answers

Answer:

the total magnetic force on the 2 sides of the wire is 0.30 N

Option a) 0.30 N is the correct answer

Explanation:

Given the data in the question;

both the sides of the right angled triangle is the same and the magnetic is in the plane of the  triangle and is perpendicular to the hypotenuse.

hence, angle between the magnetic field and both the sides of the triangle is 45 degrees.

∅ = 45°

I = 2.0 A

L = 15 cm = 0.15 m

B = 0.7 T

Total magnetic force on the 2 sides of the wire will be;

F = 2BILsin∅

we substitute

F = 2 × 0.7 × 2.0 × 0.15 × sin(45°)

F = 0.42 × 0.70710678

F = 0.2970 ≈ 0.30 N

Therefore, the total magnetic force on the 2 sides of the wire is 0.30 N

Option a) 0.30 N is the correct answer

When a 20 kg explosive detonates and sends a 5 kilogram piece traveling to the right at 105 m/s
what is the speed and direction of the other 15 kilogram piece of the explosive!

Answers

Answer:

speed: 35m/s

direction: left

Explanation:

Assuming the right side is the positive direction:

before explosion:

P = mv = 0

after explosion:

P' = 15P + 5P

(Set the velocity of the 15kg piece after explosion as v1' and the velocity of the 5kg piece after explosion as v2')

P' = 0.75mv1' + 0.25mv2'

P' = (15kg)v' + (5kg)(105m/s)

P' = 525kg/m/s + (15kg)v1'

P = P'

525kg/m/s + (15kg)v1' = 0

(15kg)v1' = -525kg/m/s

v1' = -35m/s

speed = |-35| = 35m/s

direction is to the left since the right side is the positive direction.

Which energy source can be found on the electromagnetic spectrum? A) sound energy B) chemical energy UV light energy D mechanical energy

Answers

B uv light energy
Explanation:I need 20 characters

16. Two electric bulbs marked 100W 220V and 200W 200V have tungsten
filament of same length. Which of the two bulbs will have thicker
filament?

Answers

Answer:

The second bulb will have thicker filament

Explanation:

Given;

First electric bulb: Power, P₁ = 100 W and Voltage, V₁ = 220 V

Second electric bulb: Power, P₂ = 200 W and Voltage, V₂ = 200 V

Resistivity of tungsten, ρ = 4.9 x 10⁻⁸ ohm. m

Resistance of the first bulb:

[tex]P = IV = \frac{V}{R} .V = \frac{V^2}{R} \\\\R = \frac{V^2}{P} \\\\R_1 = \frac{V_1^2}{P_1} = \frac{(220)^2}{100} = 484 \ ohms[/tex]

Resistance of the second bulb:

[tex]R_2 = \frac{V_2^2}{P_2} = \frac{(200)^2}{200} = 200 \ ohms[/tex]

Resistivity of the tungsten filament is given by the following equation;

[tex]\rho = \frac{RA}{L}[/tex]

where;

L is the length of the filament

R is resistance of each filament

A is area of each filament

[tex]A = \pi r^2[/tex]

where;

r is the thickness of each filament

[tex]\rho = \frac{R (\pi r^2)}{L} \\\\\frac{\rho L}{\pi} = Rr^2 \\\\Recall ,\ \frac{\rho L}{\pi} \ is \ constant \ for \ both \ filaments\\\\R_1r_1^2 = R_2r_2^2\\\\(\frac{r_1}{r_2} )^2 = \frac{R_2}{R_1} \\\\\frac{r_1}{r_2} = \sqrt{\frac{R_2}{R_1} } \\\\\frac{r_1}{r_2} = \sqrt{\frac{200}{484} } \\\\\frac{r_1}{r_2} = 0.64\\\\r_1 = 0.64 \ r_2\\\\r_2 = 1.56 \ r_1[/tex]

Therefore, the second bulb will have thicker filament


Please help I will mark you brainliest

Answers

I believe the answer is a

The correct answer is D, that is the point of the lowest elevation on the map.

The volume of a gas decreases from 15.7 mºto 11.2 m3 while the pressure changes from 1.12 atm to 1.67 atm. If the
initial temperature is 245 K, what is the final temperature of the gas?
O 117 K
230 K
261K
.
O 512K

Answers

Answer:

Approximately [tex]261\; \rm K[/tex], if this gas is an ideal gas, and that the quantity of this gas stayed constant during these changes.

Explanation:

Let [tex]P_1[/tex] and [tex]P_2[/tex] denote the pressure of this gas before and after the changes.

Let [tex]V_1[/tex] and [tex]V_2[/tex] denote the volume of this gas before and after the changes.

Let [tex]T_1[/tex] and [tex]T_2[/tex] denote the temperature (in degrees Kelvins) of this gas before and after the changes.

Let [tex]n_1[/tex] and [tex]n_2[/tex] denote the quantity (number of moles of gas particles) in this gas before and after the changes.

Assume that this gas is an ideal gas. By the ideal gas law, the ratios [tex]\displaystyle \frac{P_1 \cdot V_1}{n_1 \cdot T_1}[/tex] and [tex]\displaystyle \frac{P_2 \cdot V_2}{n_2 \cdot T_2}[/tex] should both be equal to the ideal gas constant, [tex]R[/tex].

In other words:

[tex]R = \displaystyle \frac{P_1 \cdot V_1}{n_1 \cdot T_1}[/tex].

[tex]R =\displaystyle \frac{P_2 \cdot V_2}{n_2 \cdot T_2}[/tex].

Combine the two equations (equate the right-hand side) to obtain:

[tex]\displaystyle \frac{P_1 \cdot V_1}{n_1 \cdot T_1} = \frac{P_2 \cdot V_2}{n_2 \cdot T_2}[/tex].

Rearrange this equation for an expression for [tex]T_2[/tex], the temperature of this gas after the changes:

[tex]\displaystyle T_2 = \frac{P_2}{P_1} \cdot \frac{V_2}{V_1} \cdot \frac{n_1}{n_2} \cdot T_1[/tex].

Assume that the container of this gas was sealed, such that the quantity of this gas stayed the same during these changes. Hence: [tex]n_2 = n_1[/tex], [tex](n_2 / n_1) = 1[/tex].

[tex]\begin{aligned} T_2 &= \frac{P_2}{P_1} \cdot \frac{V_2}{V_1} \cdot \frac{n_1}{n_2}\cdot T_1 \\[0.5em] &= \frac{1.67\; \rm atm}{1.12\; \rm atm} \times \frac{11.2\; \rm m^{3}}{15.7\; \rm m^{3}} \times 1 \times 245\; \rm K \\[0.5em] &\approx 261\; \rm K\end{aligned}[/tex].

Help please. Question about a potential energy.

Answers

P=m*g*h. So this implies that 130*10*0.200=260J. Bear in mind that g is constant.

PLEASE HELP!! :)
Which of the following options would increase the electric force the most?

a. tripling the charge on one particle

b. changing the sign of one of the particles.

c. doubling the charge on one particle

d. doubling the charge on both particles

Answers

Im not sure but i guess you should try A

Which of the following would NOT be
considered a pollutant?
A. carbon monoxide
B. sulfur dioxide
C. oxygen
D. smoke

Answers

Answer:

Answer: Oxygen

Explanation:

Oxygen would not be considered as a pollutant

Answer:

Hey there the answer is C. Oxygen

Explanation:

Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. After hydrogen and helium, oxygen is the third-most abundant element in the universe by mass. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula O 2. Diatomic oxygen gas constitutes 20.95% of the Earth's atmosphere. Oxygen makes up almost half of the Earth's crust in the form of oxides. Hope this helps! Have a great day!

When jeremiah stands in a swimming pool and looks at hid feet, his legs appear to be bent. Which is the term for this phenomenon?
A. Diffraction
B. Dispersion
C. Reflection
D. Refraction

Answers

D: Refraction
Explanation: Refraction occurs when a medium bends the light rays of an object. Like water for instance as an example of a medium.

What is the unit of measurement of mass and weight? ​

Answers

the unit of measurement for mass & weight is kilograms (kg)

Answer:

kilogram

In the International System of Units (SI), the kilogram is the basic unit of mass, and the newton is the basic unit of force. The non-SI kilogram-force is also a unit of force typically used in the measure of weight.

I beg you plz help me asap!!!
Q. How does new planet change our understanding about the universe?​

Answers

Answer:

a.

Explanation:

there would be a new planet is our solar system which could cause different gravitation pull on all the planets also there could be possible be new life form or other valuable metals that haven't been discovered on this planet. hope this helps somewhat

Well, considering there's countless planets out there that haven't been discovered on top of the ones that have been, it definitely changes our understanding of the universe by showing that there's more out there to explore and the fact that conditions in space support a lot more planets than previously thought I'm sure.

Can someone tell me How many wavelength is in the picture

Answers

I am pretty sure that the answer is 3

Hi please zoom in to see it clearly, uh you don’t have to answer them all but it would be nice !!! (no links please) :D

Answers

12.could be D
13.A
14.D
15.C
16.A

The photosphere refers to the Sun's:
core
atmosphere
surface
magnetic field

Answers

I think it is magnetic field

Answer:

The photosphere is the visible "surface" of the sun. So your answer would be C.

Explanation: its right

What is the importance of using locally available resources in creating art?​

Answers

Answer:

please give me brainlist and follow

Explanation:

Using locally available resources for art help in the preservation of environment. A significant and practical aspects of art is material significance. The items used by artists while making an art piece affects both the form and the material. Every material delivers something special in the creative process.

A spring has a spring constant of 450 N/m. How much must this spring be stretched to store 49 J of potential energy?

Answers

Answer:

W = 1/2 K x^2

x^2 = 2 * W / K = 2 * 49 J / (N/m)  = .218 / m^2

x =  .467 m

volcano has both useful and harmful effects give reason​

Answers

Answer:

harmful effects

1. that will cause air pollution

2. that will destroy our earth

Answer:

useful effects of volcano are :-

it makes soil fertile it provides valuable nutrients for the soil

harmful effects of volcano are:-

it makes air polluted it destroy the environment .

hope it is helpful to you ☺️

Why is it harder to breathe on a
mountain?
A. The air pressure is so high the lungs can't expand.
B. The air is denser and oxygen can't flow easily into the
lungs.
C. The denser oxygen molecules sink below the
surrounding air.
D. The air is less dense so there are fewer oxygen
molecules.

Answers

I think it’s d but I’m not sure

should scientist be allowed to do anything that they can?​

Answers

No, because some scientist are bad and they must have a scientific attitude like honesty, curiosity, open-mindedness, optimistic and more. And they should follow others sometimes because for their own good.

Answer:

No

Explanation:

Science operates in the context of national and international laws, agreements and conventions. It requires scientists to conduct and communicate scientific work for the benefit of society, with excellence, integrity, respect, fairness, trustworthiness, clarity, and transparency.

If 10 Coulombs flow through a circuit every 2 seconds, what is the current?
A. Not enough info
B. 5 A
C. 10 A
D. 1 A

Answers

Answer:

not enought info

Explanation:

tbh I just know it's not 5 10 or 1

Answer:

B. 5 A

Explanation:

10/2= 5

Educere

A bullet of mass 4.00 g is fired horizontally into a wooden block of mass 1.30 kg resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.170. The bullet remains embedded in the block, which is observed to slide a distance 0.240 m along the surface before stopping. Part A What was the initial speed of the bullet

Answers

Answer:

[tex]291.67\ \text{m/s}[/tex]

Explanation:

[tex]m_1[/tex] = Mass of bullet = 4 g

[tex]m_2[/tex] = Mass of block = 1.3 kg

[tex]\mu[/tex] = Coefficient of friction = 0.17

[tex]s[/tex] = Displacement of block = 0.24 m

[tex]v_1[/tex] = Velocity of bullet

[tex]v[/tex] = Velocity of combined mass

[tex]g[/tex] = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]

The energy balance of the system is given by

[tex]\dfrac{1}{2}(m_1+m_2)v^2=\mu(m_1+m_2)gs\\\Rightarrow v=\sqrt{2\mu gs}[/tex]

As the momentum is conserved in the system we have

[tex]m_1v_1=(m_1+m_2)v\\\Rightarrow m_1v_1=(m_1+m_2)\sqrt{2\mu gs}\\\Rightarrow v_1=\dfrac{(m_1+m_2)\sqrt{2\mu gs}}{m_1}\\\Rightarrow v_1=\dfrac{(4\times 10^{-3}+1.3)\times \sqrt{2\times 0.17\times 9.81\times 0.24}}{4\times 10^{-3}}\\\Rightarrow v_1=291.67\ \text{m/s}[/tex]

The initial speed of the bullet is [tex]291.67\ \text{m/s}[/tex].

A 20 ft ladder leans against a wall. The bottom of the ladder is 3 ft from the wall at time t=0 and slides away from the wall at a rate of 2ft/sec. Find the velocity of the top of the ladder at time t=1.

Answers

Answer: 0.516 ft/s

Explanation:

Given

Length of ladder L=20 ft

The speed at which the ladder moving away is v=2 ft/s

after 1 sec, the ladder is 5 ft away from the wall

So, the other end of the ladder is at

[tex]\Rightarrow y=\sqrt{20^2-5^2}=19.36\ ft[/tex]

Also, at any instant t

[tex]\Rightarrow l^2=x^2+y^2[/tex]

differentiate w.r.t.

[tex]\Rightarrow 0=2xv+2yv_y\\\\\Rightarrow v_y=-\dfrac{x}{y}\times v\\\\\Rightarrow v_y=-\dfrac{5}{19.36}\times 2=0.516\ ft/s[/tex]

Fill in the blanks using the following words: Solid, Liquids, Gasses, More, Less, Gas, Fluids, Higher, Lower, Sun, Radiation, Conductors

● Radiation transfers heat best through _________ because there is _______ space between the particles.

● Conduction transfers heat best through _______ because there is space between the particles.

● Convection transfers heat best through _______ which includes _______ and ______.

● Heat always moves from _________ temperature to _________ temperature.

● Heat from ______ travels to earth by ___________.

● Solids that transfer heat well ate known as _____________.

Answers

Answer:

Blank 1: Gasses

Blank 2: More

Blank 3: Solids

Blank 4: Fluids

Blank 5: Liquid

Blank 6: Gas

Blank 7: Higher

Blank 8: Lower

Blank 9: Sun

Blank 10: Radiation

Blank 11: Conductors

P.S. order of answers does not matter between Blank 5 and 6.

Hand pushes on a table with a force of 35n forward.reaction force

Answers

Answer:

como  ías

Explanation:

A mass weighing 24 pounds, attached to the end of a spring, stretches it 4 inches. Initially, the mass is released from rest from a point 4 inches above the equilibrium position. Find the equation of motion. (Use g

Answers

Answer:

The equation of motion is [tex]x(t)=-[/tex][tex]\frac{1}{3} cos4\sqrt{6t}[/tex]

Explanation:

Lets calculate

The weight attached to the spring is 24 pounds

Acceleration due to gravity is [tex]32ft/s^2[/tex]

Assume x , is spring stretched length is ,4 inches

Converting the length inches into feet [tex]x=\frac{4}{12} =\frac{1}{3}feet[/tex]

The weight (W=mg) is balanced by restoring force ks at equilibrium position

mg=kx

[tex]W=kx[/tex] ⇒ [tex]k=\frac{W}{x}[/tex]

The spring constant , [tex]k=\frac{24}{1/3}[/tex]

                            = 72

If the mass is displaced from its equilibrium position by an amount x, then the differential equation is

    [tex]m\frac{d^2x}{dt} +kx=0[/tex]

    [tex]\frac{3}{4} \frac{d^2x}{dt} +72x=0[/tex]

  [tex]\frac{d^2x}{dt} +96x=0[/tex]

Auxiliary equation is, [tex]m^2+96=0[/tex]

                                 [tex]m=\sqrt{-96}[/tex]

                               =[tex]\frac{+}{} i4\sqrt{6}[/tex]

Thus , the solution is [tex]x(t)=c_1cos4\sqrt{6t}+c_2sin4\sqrt{6t}[/tex]

                                 [tex]x'(t)=-4\sqrt{6c_1} sin4\sqrt{6t}+c_2[/tex]  [tex]4\sqrt{6}[/tex] [tex]cos4\sqrt{6t}[/tex]

The mass is released from the rest x'(0) = 0

                    [tex]=-4\sqrt{6c_1} sin4\sqrt{6(0)}+c_2[/tex] [tex]4\sqrt{6}[/tex] [tex]cos4\sqrt{6(0)}[/tex] =0

                                                    [tex]c_2[/tex] [tex]4\sqrt{6} =0[/tex]

                                     [tex]c_2=0[/tex]

Therefore , [tex]x(t)=c_1[/tex] [tex]cos 4\sqrt{6t}[/tex]

Since , the mass is released from the rest from 4 inches

                    [tex]x(0)= -4[/tex] inches

[tex]c_1 cos 4\sqrt{6(0)} =-\frac{4}{12}[/tex] feet

   [tex]c_1=-\frac{1}{3}[/tex] feet

Therefore , the equation of motion is  [tex]-\frac{1}{3} cos4\sqrt{6t}[/tex]

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Convert: 24 yards = _____ feet72 feet48 feet76 feet8 feet PLEASE HELP WILL MARK BRAINLIEST One hazard of space travel is debris left by previous missions. There are several thousand objects orbiting Earth that are large enough to be detected by radar, but there are far greater numbers of very small objects, such as flakes of paint. The force exerted by a 0.100-mg chip of paint that strikes a spacecraft window at a relative speed of 4.00 x 103 m/s, given the collision lasts 6.00 x 10-8 s is Fill input: x 106 N. Your friends house is 6 miles south and 8 miles east of your house how far is your friends house from your house ANSWER ASAP: What are the basicneeds of humans? What are basic needs ofanimals? How are these similar or different? QUESTION: Find the value of "A'' in the set of the supplementary angles... if you dont know dont answer i will give brainlist for it What form do some schools, especially private schools, use in addition to the FAFSA to determine how to award aid? A) FAFSA II B) Core Residency Form C) CSS/Financial Aid PROFILE D) College Access Loan (CAL) Form Simplify the following and leave your answer in smallest form 1 + 2 + 1_ _ _2 3 6 What was the compromise called that Rutherford B. Hayes made because of the close election?(A) The Jim Crow Laws Compromise(B) The Compromise of 1877(C) The Tilden-Hayes Compromise(D) The Election Compromise I'm writing a TDA on the hobbit with the theme of the negative effect of greed. Can anyone give me some examples of this? I'll give 50 points. Help is for now please Which poems Uses both lambic pentameter and blank verse Please help me on this question if you would want brianleist!! Tank yah!! ^^ 800:2 in the simplest form A wheelchair ramp is being built for entrance to a portable classroom. If the ramp has a slope of1/12 and has a horizontal length of 5 m, what is its height to the nearest tenth of a metre?a1.1 mc. 0.4 mb. 0.8 md. 0.3 m Describe the relationship between the inputs and outputs in the diagram. Then complete the diagram. If a volume of an object varies directly with its height and if the volume is 24 while the height is 3 what is k Choose the number equal to: 2/3(-3).A) -2 B)-2/9C)2/9D)2 Is it possible to be a superpower without imperialism? If you were president, how would you go about expansion and growth?(ONE PARAGRAPH PLEASE) What country built the Berlin Wall?