An oil spill has fouled 400 miles of Pacific shoreline. The company responsible has been ordered to clean the mess. Each clean-up crew costs $10000 to bring in, and $700 per crew per day. Each crew can clean 1 mile of shoreline per day. To encourage a speedy cleanup, the government is levying a fine of $1000 per day against the company. Your group has been hired by the company to determine how many crews the company should hire to minimize their costs. Find an equation that gives the cost, C of cleanup in terms of the number of crews.