Well the rule for bases with multiple exponents is:
((a^b)^c)^d = a^(b*c*d)
So in this case we have:
(((x^(1/3))^4)^5
x^(4*5*1/3)
x^(20/3)
The "transformation" for a base being raised to multiple exponents is to raise the base to the power of the product of all exponents.
