A vat containing 10,000 gallons of black ink supplies 3 different printing presses. Press 1 uses 12 gallons per minute, press 2 uses 10 gallons per minute and press 3 uses 15 gallons per minute. If the vat was full at 7:30 AM and all three presses run constantly when will the vat run dry?
12:00 P.M.
12:00 A.M.
12:20 P.M.
2:00 P.M.