Final answer:
The net profit of the neighbor's restaurant is $2.30 million.
Step-by-step explanation:
The net profit or loss of the neighbor's restaurant can be found by subtracting the expenses from the gross sales. In this case, the gross sales are $7.80 million and the expenses are $5.50 million.
Net Profit = Gross Sales - Expenses
Net Profit = $7.80 million - $5.50 million
Net Profit = $2.30 million
Therefore, the net profit is $2.30 million.