Four years ago, you took out a $10-$year mortgage of $5,000,000$ baht from Bangkok Bank $($BBL$)$ to buy a new house with an annual interest rate of $12\%$ with equal monthly payment.

After making payments for four years, interest rate in the market has significantly dropped and you are offered by Siam Commercial Bank $($SCB$)$ to refinance the outstanding loan at an annual interest rate of $6\%$ over the remaining six years with equal monthly payment.

$4\mathrm{.}1$ Calculate the monthly payment with BBL$\mathrm{.}4\mathrm{.}2$ Calculate the outstanding loan balance with BBL after paying back the loan for $4$ years.PVFVINPMTMODE$4\mathrm{.}3$ If you decide to refinance the outstanding loan with SCB$,$ how much is the monthly payment?PVFVINPMTMODE