A farmer measured the quantity of water in a tank 10 days after it was filled and found it to be 2,000 gallons. After the next 5 days, it was measured again and found to contain 1,300 gallons. Assume that the amount of water in the tank decreases at a constant rate. Find the slope of the linear relation between L, the number of liters of water consumed, and t, the number of days after the tank was filled. A.)-140gallons/day B.)-70gallons/day C.)-150gallons/day D.)-100gallons/day