Find the f'(x), f"(x), and f"(x) for the following polynomials f(x)=7x +8x - 3x -5x+2 f(x) = 4x +7x - 8x-12 The cost to remove a pollutant from the city's water system is approximated by th 0.5x 100-x C(x) = - Where x represents the PERCENT of pollutant in the water and C(x) represents th millions of dollars a.) Find the rate at which the cost of removing the pollutant is changing with percent of the pollutant in the water system b.) Find C'(80), C'(90), C'(95), and C'(99). What does your results tell you cost of removing all (or at least 99%) of the pollutant?