Annual interest rate =5.9%, monthly interest rate = annual interest rate/12=0.49 167%.

Formula Monthly repayment amount = loan amount * monthly interest rate/[1-(1+monthly interest rate)-repayment months]

Monthly repayment amount = 300,000 * 0.49167%/[1-(1+0.49167%)-156]

Monthly repayment amount = 2758.44 yuan

Total repayment = 430,365,438+06.438+0 yuan.

Total interest =130,316.9438+0 yuan.

Answer:

The annual interest rate of 5.9% is not too high.

Under the assumed conditions, the monthly repayment amount of this loan is 2,758.44 yuan; The total repayment amount is 430,365,438+06.438+0 yuan; The total interest is130,316.9438+0 yuan.