Compute all parts of given problem:
Problem: A car travels in a straight line with an average velocity of 85 km/h for 2.5 hours and then with an average velocity of 44 km/h for 1.5 hours.
Part A: What is the total displacement for the 4.0 h trip?
km
Part B: What is the average velocity for the total trip?
km/h
Please include each step and the equations you used. Thanks!