A nurse is caring for a client who has a deep vein thrombosis and is prescribed heparin by continuous IV infusion at 1,200 units/hr. Available is heparin 25,000 units in 500 mL D5W. The nurse should set the IV pump to deliver how many mL/hr? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)