Felix is purchasing a brownstone townhouse for $2,600,000.$ To obtain the$$ mortgage, Felix is required to make a $1919\%$ down payment. Felix obtains a $30-$year mortgage with an interest rate of $5\mathrm{.}5\%.$

$$a$)$ Determine the amount of the required down payment.

$$b$)$ Determine the amount of the mortgage.

$$c$)$ Determine the monthly payment for principal and interest.