The Marginal Cost for the Production of the New Super $C ^ { \prime } ( q ) = 15 - 0.0002 q$

Essay

The marginal cost for the production of the new Super Widget at Widget International is give by $C ^ { \prime } ( q ) = 15 - 0.0002 q$ , whereas the marginal revenue is $R ^ { \prime } ( q ) = 20 - 0.003 q$ , where in both cases q represents the number of units produced.
(a) Determine the change in profits when sales are increased from 700 to 1700 units.
(b) What is the change in profit when sales increase from 1700 to 2700 units? Discuss your answer.