Solve the all parts of given problem:
Problem: As an object moves with constant acceleration. At t=0 the position is x=0. At t=1 the position is x=1 and at t=2 the position is x=5.
Part A: What is the acceleration?
Part B: What is the velocity at t=0?
Part C: What is the average velocity in the first 1.5 seconds?
Please also explain, thank you in advance.