Answer:
Eric's opportunity cost of typing pages is $25 per page.
Based on all of these facts, Deborah has a comparative advantage in typing pages.
Step-by-step explanation:
Eric's opportunity cost of typing is $500 / 20 pages = $25 per page.
Since's Deborah's opportunity cost of typing pages is 20% less than Eric's, then she has a comparative advantage in typing pages.
The person, business or country with the lowest opportunity cost has the comparative advantage in producing that good.