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Lisa has three classes that each last 50 minutes. what is the total number of minutes of the three classes

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

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g