Assuming that p neq 0 and q neq 0, simplify (pq^2)^3*(4pq^2)^(-3)*(2pq)^2*(2p^2*q^3)^2
(pq^2)^3*(4pq^2)^(-3)*(2pq)^2*(2p^2*q^3)^2
= p^3 * q^(6) * (4^(-3)) * p^(-3) * q^(-6) * 4^(-3) * 2^2 * p^2 * q^2 * 2^(2) * p^(4) * q^(6)
= (1/2)^5 * p^(6) * q^(10) * 4^(-6)
= (1/32) * p^(6) * q^(10) * (1/16)
= p^(6) * q^(10) / 512