Answer:
A. 
Step-by-step explanation:
The options are:

For this exercise it is important to remember that, by definition, the Exponential parent functions have the form shown below:

Where "a" is the base.
There are several transformations for a function f(x), some of those transformations are shown below:
1. If
and
, then the function is stretched vertically by a factor of "b".
2. If
and
, then the function is compressed vertically by a factor of "b"
Therefore, based on the information given above, you can identify that the function that represents a vertical stretch of an Exponential function, is the one given in the Option A. This is:

Where the factor is:

And 
27= 3x3x3
54 = 3x3x3x2
so 27/54 = 3x3x3 /<span>3x3x3x2 by simplifying = 1/2</span>
Answer:
The first one
Step-by-step explanation:
The answer is D. Three over two
Answer: C: Negative
Step-by-step explanation: That's what I assumed you're asking due to the absolute lack of info