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(3) A twenty-year annuity pays $2,400+300k on the first day of the k-th month of the year. Thus it pays $2,700 each January 1, $3,000 each February , $6,000 each December 1. The first payment is on a January 1. Find an expres- sion for the value of this annuity just before the first payment and evaluate it if the annual effective interest rate is 5%. *8RS