Chapter 5 - Section 5.2 - More Work with Exponents and Scientific Notation - Exercise Set - Page 268: 74

$6.0\times10^{13}$

Using laws of exponents, the given expression simplifies to \begin{align*} & \dfrac{1.2\times10^{9}}{2\times10^{-5}} \\\\&= (1.2\div2)(10^{9}\div10^{-5}) \\\\&= 0.6\times10^{9-(-5)} \\\\&= 0.6\times10^{14} \\\\&= 6.0\times10^{13} .\end{align*}