#### Answer

a.
$5^{4}.5^{-2} = 5^{2} = 25$
b.
$\frac{10^{7}}{10^{4}} = 10^{3} = 1000 $
c.
$\frac{3^{2}}{3^{4}} = 3^{-2} = \frac{1}{9} $

#### Work Step by Step

a.
$5^{4}.5^{-2} = 5^{4-2} = 5^{2} = 25$
b.
$\frac{10^{7}}{10^{4}} = 10^{7}.10^{-4} = 10^{7-4} = 10^{3} = 1000 $
c.
$\frac{3^{2}}{3^{4}} = 3^{2}.3^{-4} = 3^{2-4} = 3^{-2} = \frac{1}{9} $