a)
(3x)^3=3^3x^3=27x^3
b)
(-2a)^5=-2^5a^5=-32a^5
c)
(-xy)^8=(-x)^8y^8=x^8y^8
d)
(-ab^2)^3=-a^3b^6
e)
(-3xy^2)^4=(-3)^4x^4y^8=81x^4y^8
f)
(-x^2y^3)^5=-x^{10}y^{15}
g)
(\frac{a}{2})^4=\frac{a^4}{2^4}=\frac{a^4}{16}
h)
(-\frac{x}{2})^3=-\frac{x^3}{2^3}=-\frac{x^3}{8}
i)
(\frac{-a}{2b})^4=\frac{(-a)^4}{2^4*b^4}=\frac{a^4}{16b^4}
j)
(\frac{-3a^2b^4}{cd^7})^3=\frac{(-3)^3a^6b^{12}}{c^7d^{21}}=\frac{-27a^6b^{12}}{c^7d^{21}}