Can someone help me out?

Find the multiplicative inverse of 8-12i

The function f(x) = 14,600(1.1)* represents the population of a town x years after it was established. what was the original population of the town?

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.