The nurse reconstitutes the powdered form of ceftriaxone 1 gram by engaging the vial of powdered medication into the infusion bag containing 100 mL of diluent. The client is to receive 1 gram IV by intermittent secondary infusion over 30 minutes. Which rate should the nurse regulate the gravity infusion using an IV tubing with a drop factor of 15 gtt/mL? (Enter numeric value only.)