Return on Investment
Shown Below Are Selected Data from a Recent

Return on investment
Shown below are selected data from a recent annual report of Quality Service. (Dollar amounts are in millions.)
Compute for the year:
$$\begin{array} { | l | r | r | } \hline & \begin{array} { c } \text { Beginning } \\\text { of the Year }\end{array} & { \begin{array} { c } \text { End of } \\\text { the Year }\end{array} } \\\hline \text { Total assets } & \$ 6,000 & \$ 6,600 \\\hline \text { Total stockholders' equity } & \$ 3,200 & \$ 3,700 \\\hline \text { Operating income } & & \$ 2,000 \\\hline \text { Net income } & & \$ 1,900 \\\hline\end{array}$$ (a) Return on average total assets
(b) Return on average total equity