A nurse is preparing to administer lactated Ringer's 250 mL IV to infuse over 30 min. 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.)

To calculate the infusion rate for lactated Ringer's solution, the nurse should use the following formula: infusion rate (mL/hr) = volume (mL) / time (hr). Since the volume is 250 mL and the time is 0.5 hr (30 min), the infusion rate is 250 / 0.5 = 500 mL/hr. The nurse should set the IV pump to deliver 500 mL/hr of lactated Ringer's solution to the patient.