AP PRECALCULUS High School Course. Could you answer PART A,B, AND C based on the directions and topic question?

Let r = f(0) be a polar function in the polar coordinate system, where f (0) = -1 + 5 cos(302 - 2). Lety = 9(x) be a function in the rectangular coordinate system, where g (x) = -1 + 5 cos(3x2 - 2). The domain of f is 0