A water tank initially contains a certain amount of water and is being filled at a constant rate. The relationship between the total volume of water in the tank, , in gallons, and the time, , in minutes, is represented by the equation . What is the best interpretation of 50 in this context?
The rate at which water is added to the tank.
The total volume of water in the tank after minutes.
The initial volume of water in the tank.
The time it takes to add 50 gallons of water.
