Physics
posted by Help! .
You are at the park. You are going to analyze a roller coaster. You ask the attendant for the height of the first hill and find out that it is 106.1 feet tall. Along with your group members, you pace off a train waiting to be loaded. The train is 10.5 paces long. Your group then watches the roller coaster, measuring the amount of time it takes for the train to pass a single point at the bottom of the first hill. You collect the following data:
First timing: 0.42 seconds
Second timing: 0.41 seconds
Third timing: 0.46 seconds
You also determine that the track makes a 27 degree angle with the ground on the section where the train is being towed up to the top of the first hill.
With all of this information you should now be able to answer the following questions.
1) What is the speed of the train at the bottom of the first hill?
2) If you were riding on the train, how much kinetic energy would you have at the bottom of the first hill?
3) How much potential energy did you have at the top of the first hill?
4) How much energy was lost due to friction as you came down to the bottom of the first hill?
5) Finally, what is the minimum force that must have been exerted on you to pull you up to the top of the first hill?
Please help me. im soo confused!

*update
i found the speed. it was 23.5 m/s
so with this i could find #1,2 and 3.
But I still need help with #4 and 5!