First, we expand [tex](2 \cdot 10^2)^2[/tex] as a regular scientific notation expression. By squaring each term separately, we find that this is equal to [tex]4 \cdot 10^4[/tex].
Then, we multiply the other term: [tex]4 \cdot 10^4 \cdot 10^{-9}[/tex]. Note that multiplying exponents together results in adding the powers, so we have a final answer of [tex]4 \cdot 10^{-5}[/tex].