Easy tig question i have a few more after this

Estimate the product. round the first factor to the nearest whole number, round the second factor to the nearest ten, and then multiply. 3 8/9 × 96

20 da is equal to a. 2,000 cm. b. 2 m. c. 20,000 cm. d. 20,000 mm

Diane’s bank is offering 5% interest, compounded monthly. if diane invests $10,500 and wants $20,000 when she withdrawals, how long should she keep her money in for? round to the nearest tenth of a year.