Tundra Services Company, a division of a major oil company, provides various services to the operators of the North Slope oil field in Alaska. Data concerning the most recent year appear below: Sales $18,000,000 Net operating income $5,400,000 Average operating assets $36,000,000 Compute the margin for Tundra Services Company. Compute the turnover for Tundra Services Company. Compute the return on investment (ROI) for Tundra Services Company.