Answer :
l x w x h is the formula for a cube, and considering a cube's l w and h are equivalent, each side is the cubic root of the area. So each side is 0.25 m long.
[tex]a-the\ length\ of\ each\ EDGE\ of\ the\ cube\\\\The\ volume:V=a^3\ \ \ (V=0.015625\ m^2)\\\\therefore\\\\a^3=0.015625\Rightarrow a=\sqrt[3]{0.015625}=\sqrt[3]{\frac{15625}{1000000}}=\frac{\sqrt[3]{15625}}{\sqrt[3]{1000000}}=\frac{25}{100}\\\center=\boxed{\frac{1}{4}\ (m)=0.25\ (m)}[/tex]