Answer:\quad 27a^{12}b^9
Step-by-step explanation:
\left(3a^4b^3\right)^3=3^3\left(a^4\right)^3\left(b^3\right)^3 =3^3\left(a^4\right)^3\left(b^3\right)^3 3^3=27 =27\left(a^4\right)^3\left(b^3\right)^3
