Help with finance exercises

You've collected the following information about a company: \begin{tabular}{|lr|} \hline Line item & Value \\ \hline Net sales & 150 \\ Operating costs except depreciation and amortization & 30 \\ Depreciation and amortization & 10 \\ Interest & 10 \\ \hline \end{tabular} The company's average tax rate is 23%