Let's go over each of the expressions and see if they are equal to 1/8
[tex]2^{-3}=\frac{1}{2^3}=\frac{1}{8}[/tex]So A is equivalent
[tex](-8)^1=-8[/tex]So B is not equivalent
[tex](\frac{32}{4})^{-1}=\frac{1}{\frac{32}{4}}=\frac{4}{32}=\frac{1}{8}[/tex]So C is equivalent
[tex]8^8-8^9=-117440512[/tex]So D is not equivalent
[tex]\frac{8^8}{8^9}=8^{8-9}=8^{-1}=\frac{1}{8}[/tex]So E is equivalent
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