Mr. Jackson is filling his family's pool for the summer. He's using a hose with a flow rate of 15 gallons per minute, and it takes him 120 minutes to fill the 1,800-gallon pool. The function $V(t)$ represents the volume of water in the pool, in gallons, $t$ minutes after Mr. Jackson starts filling it.

What is the domain of $V(t)$ ?
all whole numbers
all whole numbers from 0 to 120
all real numbers
all real numbers from 0 to 120
Submik

Step 1 ：The problem involves Mr. Jackson filling his family's pool with a hose that has a flow rate of 15 gallons per minute. It takes him 120 minutes to fill the 1,800-gallon pool. The function $V(t)$ represents the volume of water in the pool, in gallons, $t$ minutes after Mr. Jackson starts filling it.

Step 2 ：The domain of a function is the set of all possible input values. In this case, the input value is the time in minutes.

Step 3 ：Since Mr. Jackson starts filling the pool at time 0 and stops at 120 minutes, the domain of the function $V(t)$ should be all real numbers from 0 to 120.

Step 4 ：This is because time is a continuous variable and can take any value in this interval.

Step 5 ：$\boxed{{\displaystyle \text{The domain of }V(t)\text{ is all real numbers from 0 to 120.}}}$