can someone answer all parts please

Sam has a mortgage for $942,737.00. The term of the mortgage is 4 years, and the amortization period is 15 years. Sam will make monthly payments and the mortgage rate is r4 = 3.500%. a) When the mortgage term expires Sam takes out a new mortgage for the outstanding balance still owing. The amortization period for the new mortgage is 11 years, and the term for the new mortgage is 4 years. The interest rate remains the same. What are her new monthly payments? $ b) Sam refinances her mortgage after 2 years (without penalty). The new mortgage has amortization period 13 years, and term 2 years. The amount is the outstanding balance still owing on the original mortgage, and the new interest rate is r14) = 2.750%. What are the the new monthly payments? $