A manufacturer of DVD players has monthly fixed costs of $9800 and variable costs of $65 per

Question:

A manufacturer of DVD players has monthly fixed costs of $9800 and variable costs of $65 per unit for one particular model. The company sells this model to dealers for $100 each.
(a) For this model DVD player, write the function for monthly total costs.
(b) Write the function for total revenue.
(c) Write the function for profit.
(d) Find C(250), R(250), and P(250) and interpret each answer.
(e) Find C(400), R(400), and P(400) and interpret each answer.
(f) Find the marginal profit and write a sentence that explains its meaning?