What does k stand for in the equation -3-6(1+7k)=-19

Which of the following is true for the relation f(x)=2x^2+1

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

Ineed on the last 8 questions for this homework i’m trying to get all this done by tuesday when i got to my level 5 teacher if i have passed my tabe