Carnival Corporation & plc is one of the largest cruise companies in the world with such well-known brands as Carnival Cruise Lines, Holland America Line, and Princess Cruises. For the year ended November 30, 2008, the company reported net income of $2,330 million. Total stockholders’ equity on this date was $19,098 million, and on November 30, 2007, it was $19,963 million. No preferred stock was outstanding in either year.

Required
1. Compute Carnival’s return on common stockholders’ equity for the year ended November 30, 2008.
2. What other ratio would you want to compute to decide whether Carnival is successfully employing leverage? Explain your answer.