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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?

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

Ammonia molecules have three hydrogen atoms and one nitrogen atom. how many of each atom arein five molecules of ammonia