A mortgage for a condominium had a principal balance of $$40,800$ that had to be amortized over the remaining period of $6$ years. The interest rate was fixed at $5\mathrm{.}42\%$ compounded semi$-$annually and payments were made monthly.

a$.$ Calculate the size of the payments, rounded up to the next whole number.

$$664$

$$1,295$

$$657$

$$672$