Answer:
One
Step-by-step explanation:
Opportunity cost is the cost of the next best option forgone when one alternative is chosen over other alternatives.
If Japan decides to produce computers, it forgoes the opportunity of producing phones
Opportunity cost of one computer = 25/75 = 1 /3
Opportunity cost of producing 3 computers 3 ×(1/3)= 1 phone
I hope my answer helps you