Which of the following energy systems is used most when running a 10-second sprint?

Adenosine Triphosphate - Phosphocreatine (ATP-PC)

Explanation:

The name ATP-PC in full means Adenosine Triphosphate - Phosphocreatine (ATP-PC). ATP-PC system is made up Adenosine Triphosphate (ATP) and  Phosphocreatine (PC). This system is otherwise known as the Phosphogen system. Energy coming from the breakdown of the ATP stores within the muscles supplies energy during the first few seconds of any activity after which the breakdown of PC provides energy for another 5-8 seconds of the activity until another energy is required. ATP-PC system is not oxygenated and it is and instant energy which allows ±12 seconds of maximum effort approximately.  Examples of activities where ATP-PC is used: a short sprint, pitching a baseball or lifting a heavy weight.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

wire in brush may conduct electricity from cell to drill and vice versa electrc shock possible