line of credit question

line of credit question

Martinez Sporting Goods has a $42,500 line of credit which charges an annual percentage rate of prime rate plus 6%. Their starting balance on May 1 was $4,150. On May 5 they borrowed $3,000. On May 8 the business made a payment of $2,500, and on May 15 they borrowed $5,700. If the current prime rate is 6%, what is the new balance?