Solve the following expressions. Write your answer in scientific notation.

$13.(6\mathrm{.}125{10}^3)(2\mathrm{.}345{10}^4)$

$14.(6\mathrm{.}125{10}^3)(2\mathrm{.}345{10}^{-4})$

$15.3700\mathrm{.}13(6\mathrm{.}04{10}^4)$

$16.\frac{6\mathrm{.}2{10}^4}{0\mathrm{.}4{10}^{-5}}$