XYZ Company has an ending accounts payable balance of $36,000. Its purchases for the last three months are $30,000, $29,000 and $31,000 respectively. How long, on average, does XYZ take to pay for its purchases (Quarterly DPO)? Select one: a. 60 days b. 48 days c. 36 days d. 24 days e. 12 days