Forty percent of a house painter's business is exterior work and the other sixty percent is ...

Forty percent of a house painter's business is exterior work and the other sixty percent is interior.
 
  The average exterior paint job takes 30 hours of labor and 500 of paint and primer, but the average interior job takes only 6 hours of labor and 80 of paint and primer. If he gets 25 service calls for the coming month and 30 calls for the month after that, which of the following resource requirements is correct?
  A) The painter has supply costs of greater than 13,500 but less than 13,600 for the next two months.
  B) The painter has a labor demand of greater than 800 hours but less than 850 hours for the next two months.
  C) The painter has supply costs of greater than 13,400 but less than 13,500 for the next two months.
  D) The painter has a labor demand of greater than 850 hours but less than 900 hours for the next two months.