Let R(x),C(x), and P(x) be, respectively, the revenue, cost, and profit, in dollars, from the production and sale of x items. If R(x)=5x and C(x)=0.002x2+2.5x+60, find each of the following. a) P(x) b) R(100),C(100), and P(100) c) R(x),C(x), and P(x) d) R(100),C(100), and P(100)