A corporation creates a sinking fund in order to have $$630,000$ to replace some machinery in $8$ years. How much should be placed in this account at the end of each month if the annual interest rate is $3\mathrm{.}6\%$ compounded monthly? $($Round your answers to the nearest cent.$)$

How much interest would they earn over the life of the account?

Determine the value of the fund after $2,4,$ and $6$ years.

$2$ years

$4$ years

$6$ years

How much interest was earned during the fourth month of the $5$th year?