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You have $12,000 that you want to invest at the beginning of each of 5 years. The following alternatives are available to you. On the basis of available balance at the end of the 5th year, which alternative is the best choice? An investment that pays 8% for year 1, 7% for year 2,6% for year 3,5% for year 4, and 4% for year 5. An account that pays 4% for year 1,5% for year 2,6% for year 3,7% for year 4, and 8% for year 5. An account that pays 6% per year each year. O