Which graph has a rate of change of zero?

Answer:
Step-by-step explanation:
The first line is:
It has undefined rate of change
The second line is:
It has rate of change of zero (no change in y-value for any x-value)
Answer:
Here, the rate of change is not defined.
Here, the rate of change is zero .i.e., y is independent of x.
Therefore, 2nd graph has a rate of change of zero.