Following are selected financial data in thousands of dollars for the Hunter Corporation. 2012 2011 Current assets $ 500 $400 Fixed assets, net 700 600 Total assets 1,200 1,000 Current liabilities 300 200 Long-term debt 200 200 Common equity 700 600 Total liabilities and equity $1,200 $1,000 Net sales $1,500 $1,200 Total expenses 1,390 1,100 Net income 110 100. a. Calculate Hunter's rate of return on total assets in 2012 and in 2011. Did the ratio improve or worsen? b. Diagram the expanded Du Pont system for Hunter for 2012. Insert the appropriate dollar amounts wherever possible. c. Use the Du Pont system to calculate the return on assets for the two years, and determine why they changed.