I need help answering the following problems. Thank you in advance.

If f(x) = x2 - 5x and g(x) = 3 - x, evaluate the following. a. (f + g)(1) b. (g -f)( -4) c. (f - 9)(2) a. (1) a. (f + 9)(1) = (Simplify your answer.) b. (g - f)( - 4) = (Simplify your answer.) c. (f . g)(2) = (Simplify your answer.) d. (1) = (Type an integer or a simplified fraction.)