Please help me please help

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

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?

Nonpoint source pollution is difficult to control because it