Please help with #21

Answer:
The rate at which hose add water is = 4.8 gallons / minute
Step-by-step explanation:
From the table we can observe ;
Betwwen 5 to 10 minute
Water added is = 15072.75 - 15048.5 = 24.25 gallons
Time taken = 5 minutes .
The rate at which water added is = 24.25/5 = 4.8 gallons