Neptunecorp. has $400,000 of assets, and has no liabilities. its sales for the last year were $600,000, and its net income was $25,000. stockholders recently voted in a new management team that has promised to lower costs and get the return on equity up to 15 percent. the net profit margin the company needs to achieve 15 percent return on equity, holding everything else constant, is closest to: a.5percent. b.10 percent. c.15percent. d.22.5 percent.