For problems 15 85 16, use a geometric series to write the repeating decimal as a fraction of integers. 15. 0.99999... 16. 8126262626... 300 17. Calculate Z ( 2)k. k= 13 18. Calculate Z W. i=1 73 1 19. Calculate Z 27' 17:2 20. An ordinary annuity is a sequence of equal payments made at the end of equal time periods, where the frequency of the payments is the same as the frequency of com pounding. (a) Suppose that 500 dollars is deposited at the end of each month into an account paying 3% interest compounded monthly. 1. How much is in the account. at the end of 1 month? ii. How much is in the account. at the end of 2 months? iii. How much is in the account at the end of 3 months? iv. How much is in the account at the end of n months? Express your nal "P answer in closed form5 i.e. without sigma notation or \".. .' . (1)) Suppose that R dollars is deposited at the end of some xed time period into an account paying an interest of 3' per period. How much is in the account at the end of 1/; periods