$1)$Ali wants to buy a house, to do so he will take a loan and will repay the loan with $$20,000$ in year $1$ and amounts increasing by $$1\mathrm{.}000$ each year through year $5,$ how much can he borrow at an interest rate of $10\%$ per year?

$2)$If you want to have $2$ million in $20$ years. How much should you save each year to reach your goal at $10\%$ per year interest.