Select all the expressions equivalent to...

[tex] \frac{ {5}^{6} }{ {5}^{8} } \\ = {5}^{6 - 8} \\ = {5}^{ - 2} \\ = \frac{1}{ {5}^{2} } \\ = \frac{1}{25} [/tex]
Hope you could get an idea from here.
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