A concert promoter sells tickets and has a marginal-prot function given below, where P'(x) is in dollars per ticket. This means that the rate of change of total prot with respect to the number of tickets sold, x, is P'(x). Find the total prot from the sale of the rst 80 tickets, disregarding any xed costs. P'(x) =6x- 1064 The total prot is $ . (Round to the nearest cent as needed.) Aooffee company has found that the marginal cost, in dollars per pound, of the coffee it masts is represented by the function below, where x is the number of pounds of coffee roasted. Find the total cost of roasting 350 lb of coffee, disregarding any xed costs. C'(X) = - 0.018X + 8.25, for X 5400 The total cost is $ . (Round to the nearest cent as needed.)