C(x) = 0.18x³ + 0.02x² + 4x + 180, where x is the number of
sprockets sold, in thousands. The sale price can be modeled by
S(x) = 95.4 - 6x and the company's revenue by R(x) = x•S(x).
The company profits, R(x) - C(x), could be modeled by
(1) 0.18³ +6.02x^2 + 91.4x + 180
(2) 0.18x³ - 5.98x² - 91.4x + 180
(3) -0.18³-6.02x^2 + 91.4x - 180
(4) 0.18x³ + 5.98x² + 99.4x + 180