4. What is the net present value of the following stream of cash flows assuming the opportunity cost rate is 12%? Solve NPV using each cash flow and the NPV function in Excel (use Excel formulas and basic PV/FV techniques). Year 0: -$10,000 Year 1: $4,000 Year 2: -$2,000 Year 3: $5,000 Year 4: $3,000 Year 5: $6,000