Physics asap i really do need 90 points!

1.)in order for work to be done, an applied force must cause a change in the of an object. (1 point)

2.) a weight lifter lifts a set of weights a vertical distance of 3.85 m. if a constant net force of 350 n is exerted on the weights, what is the net work done on the weights? (show all work and include units of measure) (3 points)

3.) identify each type of energy as mechanical or non-mechanical. (5 points)

gravitational potential energy
kinetic energy
nuclear energy
chemical energy
electrical energy
a. non-mechanical b. mechanical

4.)what is the difference between kinetic energy and potential energy? (2 points)

5.) a car has a kinetic energy of 4.32 x 10^5 j when traveling at a speed of 23 m/s. what is its mass? (show all work and include units of measure) (3 points)

6.) a student wearing frictionless in-line skates on a horizontal surface is pushed by a friend with a constant force of 45 n. how far must the student be pushed, starting from rest, so that her final kinetic energy is 352 j? (show all work and include units of measure) (3 points)

7.) set hill 1 to 100 cm, hill 2 to 0 cm, and hill 3 to 0 cm. be sure the coefficient of friction is set to 0.00. run the simulation with each of the 3 cars (35 g, 50 g, and 100 g) then write a brief description of how the final speed differed for each car. (2 points)

8.) turn on show graph and select k vs t to see a graph of kinetic energy (e) versus time. click play and observe the graph as the car goes down the track. set hill 1 to 100 cm, hill 2 to 0 cm, and hill 3 to 99 cm. click play. a. what happens to kinetic energy as the car goes down the hill? b. what happens to kinetic energy as the car goes up the hill? (2 points)

9.) gravitational potential energy (u) depends on three things: the object’s mass (m), its height (h), and gravitational acceleration (g), which is 9.81 m/s2 on earth’s surface: u = mgh energy is measured in joules (j). one joule is equal to one 1 kg•m2/s2. when calculating the energy of an object, it is to convert the mass and height to kilograms and meters.
a. what is the mass of the 50-gram car, in kilograms?
b. set hill 1 to 75 cm and the other hills to 0 cm. what is the height in meters? c. what is the potential energy of the car, in joules? (show all work) (3 points)

10.)using the parameters set in question 9, calculate what the final velocity would be at the bottom of the hill using (1/2)mv^2 = mgh (show all work and include units of measure) (3 points)

11.) as the car moves down the hill, you'll notice that the car's kinetic energy increases. as a result, what happens to the car's potential energy? (1 point)

12.)decreases remains the same increases in all of our simulations we left the coefficient of friction set to 0. as a result, you should have noticed that the potential energy would transfer directly into kinetic energy as it went down the hill (and vice versa as it went up a hill.) describe what trends you would expect to see if we included a coefficient of friction (in other words, added friction into the simulation). (2 points)