I don't understand this exercise pls help me

Suppose that f(0) = −3 and f '(x) ≤ 8 for all values of x. how large can f(4) possibly be? solution we are given that f is differentiable (and therefore continuous) everywhere. in particular, we can apply the mean value theorem on the interval [0, 4] . there exists a number c such that

Tom had a total of $220 and he spent $35 on a basketball ticket . what percent of his money did he have left?

Express in the simplest form: (x^2+9x+14/x^2-49) / (3x+6/x^2+x-56)