Need some help on these 3 highlighted questions only.

Question

Only do the 3 highlighted questions

Answer 1

27 square root of (2c)^4 = (2c)^4/2 = (2c)^2

28 5th root of (256a^3) = (256a^3)^1/5 = slightly more than 3a^(3/5)

34 cube root of 8b^5 = 2b^5/3 cube root of 8 is 2