Solve the all parts of given problem:
Problem: A car traveling at 27mi/h is to stop on a 40m long shoulder of the road.
Part A: What is the required magnitude of the minimum acceleration?
Part B: How much time will elapse during this minimum deceleration until the car stops?
Any help I can get on this problem is greatly appreciated! I'm not too familiar with this problem and express your answer using two significant figures.