Answer:
$180, $360. The complete question is attached in the picture below
Step-by-step explanation:
Total amount required to reduce three units of emissions by firm 1 = Sum of marginal costs from 0-3units required.
= $60 + $50 + $40 + $30 = $180
For firm 2, Sum of marginal costs for 0-3units emissions reduction
= $120 + $100 + $80 + $60 = $360