Answer: Choice B
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Explanation:
The two rules we use are
When applying the first rule to the expression your teacher gave you, we can say that:
Then applying the second rule lets us say
Therefore,
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In short, we just multiplied each exponent inside by the outer exponent 1/2.
So that explains why the exponents go from {1/4,16} to {1/8,8} for x and y in that exact order.