Tibbs Inc. had the following data for the year ending 12/31/2015: Net income =$300; Net operating profit after taxes (NOPAT) = $160; Total assets =$2,500; Short-term investments =$200; Stockholders' equity =$1,800; Total debt =$700; and Total operating capital =$2,300. What was its return on invested capital (ROIC)? Select the correct answer. a. 6.76% b. 6.96% c. 6.56% d. 7.16% e. 6.36%