The diameter of ping-pong balls manufactured by a French company is 1.57 inches with a standard deviation of .05 inches. If a sample of 36 ping-pong balls is selected from a shipment of 600 ping-pong balls, what is the probability that the sample mean will be greater than 1.58 inches

Me with this assignment ! i only partially understand, so explain. also it's a work sample. at the championship bike race, steve and paula were fighting for first place. steve was 175 feet ahead of paula and had only 300 feet left to go. he was very tired and was going only 9 feet per second. paula was desperate to catch up and was going 15 feet per second. who won the bike race and by how far did she/he win?