$11-$ Pau is considering refinancing his mortgage. He has $240$ months left on his current loan at $8\%$ interest and his current principal balance is $$70196.$ The new rate available to him is $2\mathrm{.}5\%$ for a $240$ month mortgage. Each month, how much would Pau save on his monthly payments if he decides to refinance? State your answer as a positive number rounded to two decimal points $($e$.$g$.$ if the answer is $$2345\mathrm{.}123,$ write $2345\mathrm{.}12)$

$12-$ Regina gets a monthly payment $30$ year Fully Amortizing, $7/1$ Adjustable Rate Mortgage. The initial teaser rate is $2\mathrm{.}75\%.$ The interest then resets to $250$ basis points above $1-$year CMT$.$ Right before the rate resets at the beginning of year $8,$ Regina's remaining balance is $$2224.$ The $1$ year CMT at the time of reset is $4\%.$ What will be Regina's new monthly payment in year $8?($e$.$g$.$ if the answer is $$2345\mathrm{.}123,$ write $2345\mathrm{.}12)$