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10) SAP Inc. received a $2 million grant under its Small Business Innovation program. SAP invested the grant money and developed a system to remove metal contaminants from storm water in shipyards. The firm estimates that each shipyard spends $600,000 a year on storm water clean-up efforts. If SAP is able to sign up and retain four shipyards from the first year onwards, what is the present value (PV) of the project (net of investment) if the cost of capital for SAP is 15% per year? Assume a cost of operations and other costs for SAP equal 40% of revenue.

C) $7.6 million

Answer: C

Explanation: C) Net Present Value = - Investment + Present Value of (Revenues (1 - proportion of costs))

Net Present Value = -2 + (2.4 (1 - 0.4)) / 0.15 = $7.6 million

I have the answer, but I do not understand the explanation of the solution. Can you please explain how to get the answer in more steps.