A firm is currently buying 30 TV ads at $200 each and 20 newspaper ads at $100 each for a total advertising expenditure of $8,000. The additional sales from the last TV ad were 300 units and from the last newspaper ad were 200 units. If the firm buys 2 more newspaper ads it can increase sales by ______ units and keep advertising cost the same by reducing TV ads by _____ units.

Select one:

a.

300 ; 1

b.400 ; 2

c.100 ; 1

d.100 ; 2