we have the following:
[tex]\frac{5\cdot10^{-3}+6\cdot10^{-3}}{2.2\cdot10^4}[/tex]
operating:
[tex]\begin{gathered} \frac{5\cdot10^{-3}+6\cdot10^{-3}}{2.2\cdot10^4}=\frac{11\cdot10^{-3}}{2.2\cdot10^{-4}}=\frac{1.1\cdot10^{-2}}{2.2\cdot10^{-4}}=0.5\cdot10^{-2-4}=0.5\cdot10^{-6} \\ =5\cdot10^{-7} \end{gathered}[/tex]
Theerefore, the answer is the first option
