1. What is the acceleration of a cart that rolls down a hill if it starts at rest and reaches a speed of 2.3 m/s after 0.9 s? 2. What is the speed of an object that starts from rest and accelerates at a constant 2.7 m/s for 34 s? 3. A race car starts from rest and accelerates uniformly to 63 m/s in 3.6 s. Determine the acceleration of the car in units of m/s.