An ice machine uses 3 gallons of water every 9 hours. How many gallons of water does it use each hour? How many hours does it take to use one gallon? A) 1 9 gallon per hour; 1 hour B) 1 3 gallon per hour; 3 hours C) 3 gallons per hour; 1 9 hour D) 1 3 gallon per hour; 1 3 hour