I need help with the problems that have a question mark

\begin{tabular}{|c|c|c|c|c|} \hline \multirow[b]{2}{*}{ Revenues } & \multicolumn{2}{|c|}{\begin{tabular}{l} Instructional \\ Accounting \end{tabular}} & \multicolumn{2}{|c|}{\begin{tabular}{c} Instructional \\ Business \end{tabular}} \\ \hline & $ & 500,000 & $ & 1,000,000 \\ \hline Operating Expenses & $ & 250,000 & $ & 550,000 \\ \hline Income before Service Charges & $ & 250,000 & $ & 450,000 \\ \hline Investment & $ & 300,000 & $ & 500,000 \\ \hline ROI before service charges & & ? & & ? \\ \hline Number of professors & & 5 & & 10 \\ \hline Number of students in program & 3 & 200 & & 500 \\ \hline \end{tabular} Service department expenses Service department charge rate Revenues Operating expenses Income before service charges Service charges: Payroll Advising Income from operations ROI after service charges Advising (Driver is \# of ? \begin{tabular}{cccc} \begin{tabular}{c} Instructional \\ Accounting \end{tabular} & \multicolumn{2}{c}{\begin{tabular}{c} Instructional \\ Business \end{tabular}} \\ $ & 500,000 & $ & 1,000,000 \\ $ & 250,000 & $ & 550,000 \\ \hline$ & 250,000 & $ & 450,000 \end{tabular}