A health care provider prescribes 500 mg of an antibiotic intravenous piggyback (IVPB) every 12 hours. The vial of antibiotic contains 1 g and indicates that the addition of 2.5 mL of sterile water will yield 3 mL of reconstituted solution. How many milliliters of the antibiotic should be added to the 50 mL IVPB bag? Record your answer using one decimal place. __ mL