A pyramid has a height of 18 cm and base 12cm by 7cm find the length of the slant side​

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?

This is so hard and it’s for a test

9/10 divide by -3/15 as a mixed number