Question

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Answer 1

A) $3^{-2} *\frac{1}{3}-\sqrt{\frac{1}{9} }=\frac{3^{-2}}{3}-\frac{1}{3} =3^{-2-1}-\frac{1}{3}=3^{-3}-\frac{1}{3}  = \frac{1}{27}-\frac{1}{3}=-\frac{8}{27}$

B)$\frac{2}{5} ^{-2} *\frac{2}{5} ^{3}:\sqrt{\frac{25}{4} }=\frac{2^{-2}}{5^{-2}}*\frac{2^{3}}{5^{3}}:\frac{5}{4}=\frac{5^{2}}{2^{2}}*\frac{2^{3}}{5^{3}}*\frac{4}{5}= \\\frac{25}{4}*\frac{8}{125}}*\frac{4}{5}=\frac{25}{125}}*\frac{8}{5}=\frac{8}{25}$