the total profit in dollars on the sale of item

2) The cost price of a Saturn is $13 000. When the dealer sells each car for $25 000, he sells 21 cars per month. For each reduction of $1000 in the selling price, the dealer sells 3 more cars each month. a) Determine the Profit equation for this function. b) Explain how the profit function was determined. Explain each variable. c) Determine the selling price of a car for maximum monthly profit.

Assume that it costs a company approximately C(x) = 400,000 + 180x + 0.001x² dollars to manufacture x smartphones in an hour. (a) Find the marginal cost function. Use it to estimate how fast the cost is increasing when x = 10,000. $ per smartphone Compare this with the exact cost of producing the 10,001st smartphone. The cost is increasing at a rate of $ per smartphone. The exact cost of producing the 10,001st smartphone is $ Thus, there is a difference of $ (b) Find the average cost function C and the average cost to produce the first 10,000 smartphones. C(x) C(10,000) $ (c) Using your answers to parts (a) and (b), determine whether the average cost is rising or falling at a production level of 10,000 smartphones. The marginal cost from (a) is ---Select--- O than the average cost from (b). This means that the average cost is ---Select--- O at a production level of 10,000 smartphones.