Suppose that in addition to repairing your car, you can also spend money advertising. If you repair your car for Hours and spend A dollars advertising, your benefit(the amount you receive when you sell your car) is B(H,A)=220H-H^2+2A. Both H and A are finely divisible. What is your marginal benefit of repair hours when H=4 and A=100?

Suppose that in Problem above, repair work costs $100 per hour and you have $1500 to allocate between repair work and advertising. Write down the Conostrained optimization Problem you face. What is your best choice of repair hourtising? Interpret the condition that characterizes your best choice in terms of marginal benefits and marginal (opportunity) costs of repair work.