Cambridge Manufacturing Company, Inc. has 200 labor-hours available. There is no limit on machine hours. Cambridge can sell all of Product B that it wants, but it can only sell 30 units and 20 units of Products A and C, respectively.

Question

Cambridge Manufacturing Company, Inc. has 200 labor-hours available. There is no limit on machine hours. Cambridge can sell all of Product B that it wants, but it can only sell 30 units and 20 units of Products A and C, respectively. 
                                 Product-A               Product-B               Product-C

Contribution Margin Per Unit    $20                          $10                          $16

Labor Hours Per Unit                4                             5                               4

Machine Hours Per Unit           10                           8                                2

Which product (s) and how many should Cambridge produce given the limited supply of labor-hours?

(Points : 4) 
      30 Units of Product A.
      30 Units of Product A; 20 Units of Product C.
      30 Units of Product A; 16 Units of Product C.
      40 Units of Product B.