Hi I need help on this !! <3

1. Two students, Michael and Penelope, are each asked to place a 20 kg rock onto a platform 1.2 m above the ground. Michael lifts the rock directly onto the platform, finding it extremely difficult. Penelope sets up a 3 m long frictionless inclined plane and easily pushes the rock onto the platform. Which student did more work?

1. Penelope did more work than Michael because she moved the rock over a greater distance.
2. Michael did more work than Penelope because lifting the rock was far more strenuous.
3. The both did the same amount of work.
4. Neither of them did any work.

2.A ball with a mass of 1.00 kg has an initial velocity of 10 m/s. If its velocity changes to 15 m/s, the work done on the ball is ________J.

3.You are standing on a scale in an elevator. You have a mass of 75 kg. When the elevator starts to accelerate downwards at 4.0 m/s2, the scale would show an "apparent" mass of _______ kg.

4.Which of the following would NOT result in reduced friction between a car tire and the road's surface?

1. Gravel on the road.
2. Reduced tire pressure.
3. Tire treads worn down to balding.
4. A layer of water on the pavement

5.A 125 kg box is sliding down a 27 ramp at a constant velocity of 1.12 m/s. The friction force acting on it is _________N [up].

6.Stopping while wearing in-line skates involves bringing a rubber brake pad into contact with the ground to cause friction, which eventually brings the skater to a halt. While Sara is in-line skating on a horizontal surface at 5.0 m/s, she sees a pothole 5.0 m ahead and immediately starts braking. What frictional force does the brake pad have to generate to stop Sara (who has a mass of 50 kg) in a distance of 5.0 m?

1. 63 N
2. 0.10 kN
3. 1.3 10² N
4. 0.25 kN

7.An object starts from rest and moves eastward with a uniform acceleration of 4.0 m/s². When it reaches a velocity of 12 m/s, it has travelled a displacement of _____m [E].

8.Aircraft carriers are very large ships that launch jets. The length of an aircraft carrier is 150 m. A jet taking off accelerates uniformly from rest and travels the length of the aircraft carrier in 2.00 s. What is the magnitude of the jet's velocity when it leaves the ship?

1. 340 km/h
2. 400 km/h
3. 540 km/h
4. 600 km/h

9.A bicyclist goes 200 m west, 120 m south, and 80.0 m east in 1.00 minute. The positive difference between the magnitude of the average speed and the average velocity of the bicyclist is __________m/s.