Answer:
um
Step-by-step explanation:
The depth of a river changes after a heavy rainstorm. Its depth, in feet, is modeled as a function of time, in hours
y is the depth in feet and x is the time in hours
From the table we can see that
In 9 hours, the depth is 18 feet
In 18 hours , the depth is 21 feet
(9,18 ) and (18,21)
Average rate of change = 
= 
= 
= 
the average rate of change for the depth of the river is
feet per hour
Answer:
The answer is D
Step-by-step explanation:
Plug all of the numbers in and they all work with the problem.