Answer and Explanation:
Opportunity cost is the net benefit arise from the loss suffered from the selective option.
In the given situation, the Megan's opportunity cost of making a pizza is
= 3 hours to make a pizza ÷ 5 hours to brew a gallon of root beer
= 3 ÷ 5 gallons
This is the answer but the same is not provided in the given options
And, the Susan opportunity cost of making a pizza is
= 4 hours to make the pizza ÷ 8 hours to brew a gallon of root beer
= 4 ÷ 8 gallons
= 1 ÷ 2 gallons