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huilan is 11 years younger than thomas. the sum of their ages is 87. what is thomas's age?

What is the missing constant term in the perfect square that starts with x^2 -20x

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

What is the best approximation for the area of a circle with a radius of 4 m ? use 3.14 to approximate pi