Answer:
The answer is D, 
Step-by-step explanation:
By graphing each one in a graphing tool like Desmos, you can determine which one it is.
If your looking for an actual explanation on how it is found, I can't really help you on that one.
Answer:

Step-by-step explanation:
The exponential function that decrease by 15% every time x increases by 1 is given by:

We simplify the parenthesis to get:

Therefore the decrease by 15% every time x increases by 1 is

The second choice is correct.
Answer:
$2.64
Step-by-step explanation:
0.44 times 6.