A non-isotropic solid metal cube has coefficients of linear expansion as :
5 $$ \times $$ 10^-5/^oC along the x-axis and 5 $$ \times $$ 10^-6/^oC along the y and the z-axis. If the coefficient of volume expansion of the solid is C $$ \times $$ 10^-6/^oC then the value of C is