A community swimming pool starts with 250 gallons of water. Julian starts filling the pool at a rate of 500 gallons per hour.

What is the rate of change in this linear function? In other words, by how much does the number of gallons of water in the pool change for every hour?
1
?
1
?
1
?
t
g
0
1
2
3
4
5
6
7
8
9
10
0
250
500
750
1,000
1,250
1,500
1,750
2,000
2,250
2,500
Time in hours
Gallons of water in the pool
The rate of change is
.