need the answer for b & c with explanation , thank you sir!

Question-2: Home Health, Inc., has come to Jane Ross for a yearly financial checkup. As a first step, Jane has prepared a complete set of ratios for fiscal years 201 1 and 2012. She will use them to look for significant changes in the company's situation from one year to the next. Home Health, Inc. Financial Ratios Ratio 2011 2012 Current ratio 3.25 3.00 Quick ratio 2.50 2.20 Inventory turnover 12.80 10.30 Average collection period 42.6 days 31.4 days Total asset turnover 1.40 2.00 Debt ratio 0.45 0.62 Times interest earned ratio 4.00 3.85 Gross profit margin 68% 65% Operating profit margin 14% 16% Net profit margin 8.3% 8.1% Return on total assets 11.6% 16.2% Return on common equity 21.1% 42.6% Price/earnings ratio 10.7 9.8 Market/book ratio 1.40 1.25 a. To focus on the degree of change, calculate the year-to-year proportional change by subtracting the year 201 1 ratio from the year 2012 ratio, then dividing the difference by the year 201 1 ratio. Multiply the result by 100. Preserve the positive or negative sign. The result is the percentage change in the ratio from 2011 to 2012. Calculate the proportional change for the ratios shown here. b. For any ratio that shows a year-to-year difference of 10% or more, state whether the difference is in the company's favor or not. c. For the most significant changes (25% or more), look at the other ratios and cite at least one other change that may have contributed to the change in the ratio that you are discussing