Answer:
The number of gallons Masha buys
Step-by-step explanation:
Since we know that the spring water for Masha's fish tank costs 1.56$, we can infer that when we multiply 1.56$ by a variable, the answer will give us the total cost of filling up the tank. That means that the variable g must represent the number of gallons of spring water Masha buys to fill up her tank. Hope this helps!