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8. (8 marks) For this question, show your work and circle your answer. A business manager uses straight-line depreciation and is considering a capital investment for which the following relevant cash flow data have been estimated: 4 years Estimated useful life: Initial investment: $500,000 Savings year 1: $200,000 Savings year 2: $150,000 Savings year 3: $125,000 Savings year 4: $105,000 Residual value after 4 years $20,000 a. How much is the accounting rate of return for the above investment? b. How much is the payback period of the above investment