To apply the Power Rule of Exponents, we use the following formula:
\[ (a^m)^n = a^{m \cdot n} \]
In the expression \((10^9)^7\), we can apply the power rule:
\[ (10^9)^7 = 10^{9 \cdot 7} = 10^{63} \]
So, the correct answer from your options is:
10 superscript 63 baseline (10^{63}).