need help please

Find f'( - 2) if f(x) = X - - 7x. 8 f'(-2) = (Simplify your answer. Type an integer or a fraction.)A ball is thrown vertically upward from the ground at a velocity of 128 feet per second. Its distance from the ground at t seconds is given by s(t) = - 16t- + 128t. (a) How fast is the object moving 1 second after being thrown? (b) When will it hit the ground? (c) What is its velocity upon impact? (a) Find the function v(t) that gives the ball's velocity at time t. v(t) = The ball's velocity at 1 second is feet per second. (Type an integer or a decimal.) (b) It takes the ball second(s) to reach the ground. (Type an integer or a decimal.) (c) Upon impact, the velocity of the ball is feet per second. (Type an integer or a decimal.)