Answer
(2m+5n)(4m$^2$-10mn+25n$^2$)
Work Step by Step
8m$^3$+125n$^3$
This expression is a sum of cubes. If the cube root of the first term is a and the cube root of the second term is b, then the factorization is
(a+b)(a$^2$-ab+b$^2$). So since
$\sqrt[3] {8m^3}$=2m
$\sqrt[3] {125n^3}$=5n,
(2m+5n)(4m$^2$-10mn+25n$^2$).