A loan granted by the university under section 15-52-10 and sections 15-52-15 through 15-52-28 must be upon the condition that the full amount of the loan must be repaid in cash with interest not to exceed six percent annually from the date of each payment pursuant to a loan agreement. The school of medicine and health sciences advisory council may annually establish an interest rate at a level lower than six percent. The repayment must be in yearly installments on a schedule set by the university with the first installment becoming due and payable one year from the date on which the applicant begins practice, but may not exceed six years from the date of graduation or one year from the date of graduation from a dental school if a dental student.