Respuesta :

I believe your answer is C. 0.4
So the volume is 0.064m^3
to solve for the side length
V = length * length * length
so 
0.064 = l * l * l
we would take the cube root of 0.064
so length = 0.4m 
to check 
0.4 * 0.4 * 0.4 =?= 0.064
0.064 = 0.064

Hope this helps :)