Answer:
C. -32
Explanation:
Using the rule of exponents for a power of a power, we can simplify the expression like this:
(-8)^(5/3) = ((-8)^(1/3))^5 = (-2)^5 = -32
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A suitable calculator can evaluate this for you.
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Additional comment
Some calculators use logarithms to compute powers. The logarithm of a negative number is undefined, so direct computation of this expression would give an error on such a device. You would have to recognize that the root and power are odd, so the result will be negative. Then you could calculate -(8^(5/3)) without error.
The rule of exponents used here is ...
(a^b)^c) = a^(bc)