Some one pls help 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

A(1,1) b(-3,0) c(-4,-1) d(3,-2) drag it to correct position

Suppose the equation ||x-a|-b|=2008 has 3 distinct real roots and a not =0. find the value of b.