Mark decides to mow lawns to earn money. The initial cost of his lawnmower is $300. Gasoline and maintenance costs are $10 per lawn.

Jimmy charges $40 per lawn.

• Determine the function C(x) for the total cost of mowing x lawns.

• Determine the revenue function R(x) for mowing x lawns.

• Determine the total profit function P(x) for mowing x lawns.