Ответ:

ж) \(x^8\cdot(x^2)^3=x^8\cdot x^6=x^{14}\).

з) \((2x)^6=2^6x^6=64x^6\).

и) \((3ab^5)^4=3^4a^4b^{20}=81a^4b^{20}\).

к) \(\left(\frac{a}{4}\right)^3=\frac{a^3}{4^3}=\frac{a^3}{64}\).

л) \(\left(\frac{4a^3}{3b^7}\right)^3=\frac{4^3a^9}{3^3b^{21}}=\frac{64a^9}{27b^{21}}\).