A metal refining plant emits sulfur dioxide into the air and has decided to install air

scrubbers to reduce the amount of pollution. Each scrubber costs $180,000 and the

Environmental Protection Agency (EPA) fines the plant $5,000 for every part of pollution

emitted per million.

# of Air Scrubbers Amount of pollution parts per million

0 150

1 100

2 60

3 30

4 10

5 0

Based on the information above, how many air scrubbers should the plant install in

order to minimize the total cost of pollution?

1

2

3

4

5