Solve the following problem given below:
Problem: An 860 kilogram car is at the top of a 30 m long, 2.5 incline. Its parking brakes fail and it starts rolling down the hill. Halfway down it strikes and sticks to a 1260 kg parked car. Ignoring friction,
Part I: What is the speed of the joined cars at the bottom of the incline?
Part II: What is the first cars speed would have been at the bottom had it not struck the second car?
Please show how you get the answer.