12years ago Justin Timberlake put money into an account paying 6.5% interest compounded biannually. If the account has $18,000 now, how much money did Justin Timberlake deposit?

The computer that controls a bank's automatic teller machine crashes a mean of 0.6 times per day. what is the probability that, in any seven-day week, the computer will crash less than 5 times? round your answer to four decimal places