1. The problem statement, all variables and given/known data A teenager has a car that accelerates at 3.00 m/s2 and decelerates at -4.50 m/s2. On a trip to the store, he accelerates from rest to 16.5 m/s, drives at a constant speed for 5.00 s, and then comes to a momentary stop at the corner. He then accelerates to 18.0 m/s, drives at a constant speed for 15.0 s, and decelerates for 2.67 s. Then he continues for 4.00 s at this speed and comes to a stop. 2. Relevant equations (a) How long does the trip take? (b) How far has he traveled? (c) What is his average speed for the trip? (d) How long would it take to walk to the store and back if he walks at 1.50 m/s? 3. The attempt at a solution I don't know which equations and what numbers to use. Any help on how I can find out which numbers are the ones I need and which equation I should use?