Answer:
$ 125,000
Explanation:
Given,
The amount of rent = $ 25,000,
The salary of assistant = $ 30, 000
Expenses = $ 20,000,
Also, her best alternative is to work elsewhere and to earn a salary of $50,000 per year.
Thus, the investment in the firm = 25000 + 30000 + 20000 + 50000
= $ 125,000,
Now, if she earns zero economic profit,
Then her revenue = investment
= $ 125,000