Can someone check my answer? also tell me what property i used.

Measure of angles 31 (x+4) (3x+9) me

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

Which part of a 2-column proof is the hypothesis of the conjecture? a) given b) reasons c) prove d) statements ! i think it's b but i'm not quite