Answer:
C. $4000
Explanation:
Given that
Total opportunity cost = salary plus interest forgone, that is 50,000 + 6% of 100,000
= 50,000 + 6000 = 56,000.
Total revenue received = 60,000
Recall that
Economic profits = Revenue - (implicit + explicit cost)
And that
Implicit cost = opportunity cost = 56,000
Explicit cost = 0 (from the question, revenue covered it)
Thus
Economic profit = 60000 - 56000
= $4000