л) ($$\frac{3a^2}{2b^3}$$)^4 =

$$ (\frac{3a^2}{2b^3})^4 = \frac{(3a^2)^4}{(2b^3)^4} = \frac{3^4 \cdot (a^2)^4}{2^4 \cdot (b^3)^4} = \frac{81a^8}{16b^{12}} $$

Ответ: $$\frac{81a^8}{16b^{12}}$$