Please answer this fast I have a exam

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?

Light waves travel than sound waves.