How is the volume scale factor calculated?

Arandom high school question but a hard one

Suppose that 3% of all athletes are using the endurance-enhancing hormone epo (you should be able to simply compute the percentage of all athletes that are not using epo). for our purposes, a “positive” test result is one that indicates presence of epo in an athlete’s bloodstream. the probability of a positive result, given the presence of epo is .99. the probability of a negative result, when epo is not present, is .90. what is the probability that a randomly selected athlete tests positive for epo? 0.0297

Thirteen bowlers were asked what their score was on their last game. the scores are shown below 190,150,154,194,181,190,170,151,170,178,161,180 find the range of the bowlers score a.56 b.44 c.34 d.23