Final answer:
Gary's distance traveled is 145m. His displacement is 0m.
Step-by-step explanation:
The distance traveled by Gary can be calculated by adding the distances covered while going to the market and returning back. Therefore, the total distance traveled by Gary is 125m + 20m = 145m. The displacement is the straight line distance between the start and end points. In this case, since Gary traveled west and then returned east, his displacement is 0m because he ended up at the same point where he started.