12. [-/1 Points] DETAILS Math 110 Course Resources - Indefinite Integrals Course Packet on initial value problems The daily marginal revenue function associated with selling x widgets is given by R'( x ) = -6x2+12x+ 30 where R'(x) is measured in dollars per unit per day and x denotes the number of widgets produced and sold. (a) Determine the revenue function, R(x), associated with producing and selling x widgets. R (X ) = (b) Determine the demand function relating unit price, p(x), to the quantity demanded, x. P(X =