Answer:
a=1/2 b=5/4 c=2^5/4 . ??
Step-by-step explanation:
I am not sure if the a is supposed to be a second exponent but I solved this as if it wasn't.
I'm assuming you meant to write 8^(-2) or
where the -2 is the exponent over the 8.
If my assumption is correct, then we use the rule 
So,

<h3>Answer: Choice D. 1/64</h3>