Compute each part of given problem:
Problem: A runner runs 1.26 km in 2.5 min and then takes 4.6 min to walk back to the starting point.
Part I: What is the magnitude of the average velocity of the runner for the first 2.5 min?
Part II: What is the magnitude of the runner's average velocity for the time spent walking?
Part III: What is the magnitude of the average velocity for the total trip?
Part IV: What is the average speed for the total trip?
Any help I can get on this problem is really appreciated! I'm not too familiar with this problem. Thanks in advance.