The marginal profit of a certain company is given by dy/dx= 100/32-4x where x represents the amount of money (in thousands of dollars) that the...

The marginal profit of a certain company is given by dy/dx= 100/32-4x where x represents the amount of money (in thousands of dollars) that the company spends in advertising. Find the profit for an advertising expenditure of $4000 if the profit is $1000 when nothing is spent on advertising.