Write the Word or Phrase That Best Completes Each Statement $P(x)=R(x)-C(x)$

Short Answer

Write the word or phrase that best completes each statement or answers thequestion.
-If the profit function is $P(x)=R(x)-C(x)$ , where $R(x)$ is the revenue function and $C(x)$ is the cost function, relate the marginal profit to the marginal revenue and the marginal cost.