why is net income this value? how do you get this answer?

3 Calculate net income/(loss) for the year from the following: Sales revenue Operating expenses Dividend Income Dividend pald to Shareholders Opening balance of Total Assets Opening Balance of Stockholders' Equity Net income $ 79,500 $ 230,000 $ 156,000 $ 5,500 $ 40,000 $ 210,000 $ 78,000