The exponential functions change is represented by decay and the percentage rate of decrease is 1.00619%.
Step-by-step explanation:
Step 1:
To determine if the function represents growth or decay, we substitute values to x.
If the values increase with an increase of x, it represents growth.
If the values decrease with an increase of x, it represents decay.
Step 2:
If

If 

So as x increases the value of y decreases, so it represents decay.
Step 3:
The percentage rate of change is determined by dividing the difference of two consecutive values by the first value.
The percentage rate of change 
Substituting the values, we get
The percentage rate of change
.
As the values of y decrease with an increase in x, it is the percent decrease per unit.
If your question looks like mine (shown in picture).Your answer would be number 4.
Hope this helps!
CTPehrson
Yes it is. In order for something to be a function, no X values can be the same, which is the case here.