DE10 The cost in dollars to manufacture a certain item is CM = 120 + 0.02x². This relation is valid up to 70 items per month. Find the cost to manufacture the 10th, 40th, and 70th items. This is called the marginal cost, the cost to make the next item.

The general expression for the cost per item is the derivative of the cost function with respect to x: d(CM)/dx.