This problem is about the rate of the current. It's important to know that refers to the quotient between the electric charge and the time, that's the current rate.
[tex]I=\frac{Q}{t}[/tex]Where Q = 2.0×10^−4 C and t = 2.0×10^−6 s. Let's use these values to find I.
[tex]\begin{gathered} I=\frac{2.0\times10^{-4}C}{2.0\times10^{-6}\sec } \\ I=1.0\times10^{-4-(-6)}A \\ I=1.0\times10^{-4+6}A \\ I=1.0\times10^2A \end{gathered}[/tex]As you can observe above, the division of the powers was solved by just subtracting their exponents.