1 (y) = -36y – 100 + 10y 2 – y 3 3 1 = -36(18) – 100 + 10(18)2 – (18)3 3 = 548 c. What is the marginal cost of the firm at this output level?

1 (y) = -36y – 100 + 10y 2 – y 3 3 1 = -36(18) – 100 + 10(18)2 – (18)3 3 = 548 c. What is the marginal cost of the firm at this output level? The marginal cost is equal to the derivative of the cost function, cost C (y) D. What is the variable cost of production at this output level?