Problem 9-20A Return on investment Sorrento Corporation's balance sheet indicates that the company has $500,000 invested in operating assets. During Year 2, Sorrento earned operating income of $50,000 on $1,000,000 of sales. Required a. Compute Sorrento's profit margin for Year 2. b. Compute Sorrento's turnover for Year 2. c. Compute Sorrento's return on investment for Year 2. d. Recompute Sorrento's ROI under each of the following independent assumptions: (1) Sales increase from $1,000,000 to $1,200,000, thereby resulting in an increase in operating in- come from $50,000 to $56,000. (2) Sales remain constant, but Sorrento reduces expenses, resulting in an increase in operating in- come from $50,000 to $52,000. (3) Sorrento is able to reduce its invested capital from $500,000 to $400,000 without affecting operating income