How do i find this answer?
not just looking for answer also need explanation

A) if $50000 is invested in a bank account that pays 9.3% of interest compounded on a six-monthly basis, how much money will be in the account after 3 and 12 years? b) if matusalen's father had put $2.0 in the bank when he was born and there, how long would matusalen have had to his death (969 years later) if the interest was 7% per year composed each month and weekly?

If a || b and b | y, then ? a) x || y. b) x | a. c) a | y. d) a || y.

Find the area of a parallelogram with base 15 yards and height 21 2/3