6. The following table summarizes working capital and revenue for the following firms in the chemical indus- try, as well as information on betas, expected growth. and size Noncash Expected Working Growth Market Firm Capital Revenues Beta (%) Value Arco Chemical $579 3,423 0.80 13.00 $4,517 Dow Chemical 2.075 20,015 1.25 16.00 19,398 DuPont 3.543 39,333 1.00 17.50 44.946 Georgia Gulf 127 955 1.70 26.50 1.386 Lyondell Petro 264 3,857 1.10 23.50 2,080 Monsanto 2,948 8,272 1.10 11.50 9,296 Olin Corp 749 2,658 1.00 22.00 1,205 Sterling Chemical 21 701 0.95 43.00 724 Union Carbide 329 4,865 1.30 16.00 4,653 a. Estimate the average and standard deviation in working capital ratios across these firms. b. What proportion of the differences in net working capital investments across firms can you explain using the information you have been provided in the table? c. How would you use this information to estimate the optimal working capital as a percent of rev- enues for DuPont? 6. The following table summarizes working capital and revenue for the following firms in the chemical indus- try, as well as information on betas, expected growth. and size Noncash Expected Working Growth Market Firm Capital Revenues Beta (%) Value Arco Chemical $579 3,423 0.80 13.00 $4,517 Dow Chemical 2.075 20,015 1.25 16.00 19,398 DuPont 3.543 39,333 1.00 17.50 44.946 Georgia Gulf 127 955 1.70 26.50 1.386 Lyondell Petro 264 3,857 1.10 23.50 2,080 Monsanto 2,948 8,272 1.10 11.50 9,296 Olin Corp 749 2,658 1.00 22.00 1,205 Sterling Chemical 21 701 0.95 43.00 724 Union Carbide 329 4,865 1.30 16.00 4,653 a. Estimate the average and standard deviation in working capital ratios across these firms. b. What proportion of the differences in net working capital investments across firms can you explain using the information you have been provided in the table? c. How would you use this information to estimate the optimal working capital as a percent of rev- enues for DuPont