d
(d) \({n_2} = {n_1}{\left[ {\frac{{{L_1}}}{{{L_2}}}} \right]^1}{\left[ {\frac{{{T_1}}}{{{T_2}}}} \right]^{ - 2}}\)

\( = 10{\left[ {\frac{{meter}}{{km}}} \right]^1}{\left[ {\frac{{\sec }}{{hr}}} \right]^{ - 2}}\)

\({n_2} = 10{\left[ {\frac{m}{{{{10}^3}m}}} \right]^1}{\left[ {\frac{{\sec }}{{3600\sec }}} \right]^{ - 2}}\)

\( = 129600\)