Find 4 [FO f(x) dx for the function f(x) graphed below. [Hint: No calculus is necessary-just as we used integrals to find areas, we can use areas to find integrals. The curve shown is a quarter circle.] square units y 2 2 3 4 X An average child of age x years grows at the rate of 6x-1/2 inches per year (for 2 x 16). Find the total height gain from age 9 to age 16. inches A company's marginal cost function is MC(x) (given below), where x is the number of units. Find the total cost of the first hundred units (x = 0 to x = 100). (Round your answer to the nearest cent.) MC(x) = 2e-0.02x X