\(\frac{9^3.4^6.8^2}{6^6.2^4}=\frac{\left(3^2\right)^3.\left(2^2\right)^6.\left(2^3\right)^2}{\left(3.2\right)^6.2^4}=\frac{3^6.2^{12}.2^6}{3^6.2^6.2^4}=\frac{2^{12}}{2^4}=2^8=256\)
\(\frac{9^3.4^6.8^2}{6^6.2^4}=\frac{\left(3^2\right)^3.\left(2^2\right)^6.\left(2^3\right)^2}{\left(2.3\right)^6.2^4}\) \(=\frac{3^6.2^{12}.2^6}{2^6.3^6.2^4}\) \(=\frac{2^{12}}{2^4}=2^8\)