How do u do that? i dont understand it

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?

At 6 1/2 cents per pound of string beans how much does 7 pounds cost

The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?