The annual interest of the student loan of China Development Bank is 40,000 yuan in 480 yuan. The calculation formula of interest is: principal multiplied by interest rate equals interest payable, and the national benchmark interest rate is 4.9%. CDB * * * has a loan of 40,000 yuan, that is, one-year loan 1 10,000 yuan, with a monthly interest rate of about 40 yuan and one-year 480 yuan. Therefore, the annual interest of the student loan from China Development Bank in 480 yuan is 40,000 yuan.