Answer:
(a) and (b) are not equivalent
(c) is equivalent
Step-by-step explanation:
Given

Required
Determine an equivalent or nonequivalent expression

We have:

Apply law of indices

<em>This is not equivalent to </em>
<em></em>

We have:

Apply law of indices

<em>This is not equivalent to </em>
<em></em>
<em></em>
<em />
<em />
We have:
<em />
<em />
Apply law of indices
<em />
<em />
<em />
<em />
<em>Evaluate the numerator</em>
<em />
<em />
<em />
<em>This is an equivalent expression</em>
Nonprportional is what I would think