What series of equal annual payments is equivalent to a series of decreasing payments as follows: 5000, 4000, 3000, 2000, 1000 is the interest rate is 6%. (a) 3000 (b) 3000(1 + .06 = 3180) (C) (50000(F|P6%^4) + 4000(F(P6%3) + 3000(F|P6%2) + 2000(F|P6%1) + 1000)/5 (d) 5000(A|P6%5) - 1000(A|G5%5) Consider a machine that has a first cost of 150,000, has an operating and maintenance cost of 17, 500 per year and an estimated salvage value of 25,000 at the end of 30 years. Assume the interest rate is 6% per year. What is the future equivalent cost of the investment the planning horizon is 30 years? (costs are Negative, Salvage value is positive)