Please Help me! I don't understand and am giving up the rest of my points for help!

Find the third, fifth and seventh term sequence described by each rule a(n)=n+1

Find and simplify an expression for the area of five rows of x squares with side lengths of x centimeters.

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