Thực hiện phép tính

f) \(\frac{{\sqrt {{3^2}} + \sqrt {{{39}^2}} }}{{\sqrt {{{91}^2}} - \sqrt {{{( - 7)}^2}} }}\);

k) \({\left( {\frac{3}{5}} \right)^{10}}.{\left( {\frac{5}{3}} \right)^{10}} - \frac{{{{13}^4}}}{{{{39}^4}}} + {2014^0}\)

\( = {\left( {\frac{3}{5}.\frac{5}{3}} \right)^{10}} - {\left( {\frac{{13}}{{39}}} \right)^4} + 1\)

\( = 1 - {\left( {\frac{1}{3}} \right)^4} + 1\)

h) \(0,8:\left\{ {0,2 - 7\left[ {\frac{1}{6} + \left( {\frac{5}{{21}} - \frac{5}{{14}}} \right)} \right]} \right\}\)

\( = 0,8:\left\{ {0,2 - 7\left[ {\frac{1}{6} + \left( { - \frac{5}{{42}}} \right)} \right]} \right\}\)

\[ = 0,8:\left\{ {0,2 - 7\left[ {\frac{1}{{21}}} \right]} \right\}\]

\[ = \frac{4}{5}:\left\{ {\frac{1}{5} - \frac{1}{3}} \right\}\]