Show all working steps to justify your answers. 1. Use the four-step process to find f'(x) and then f'(-3) for f(x) = x2 - 8x (7points) 2. A company's total sales (in millions of dollars) t months from now are given by S(t) = 2vt + 6 (13points) (A) Use the four-step process to find S'(t) 7pts. (B) Find (i) S (10) (ii) s'(10) and (iii) Write a brief verbal interpretation of these results. 5pts. (C) Use the results in part (B) to estimate the total sales after 11 months. 1pts. Four- Step Process Step 1 Find f(x + h) Step 2 Find f(x + h) - f(x) Step 3 Find f(x + h) - f(x) h Step 4 Find f'(x) = lim f ( x + h) - f(x ) h->0 h