Consider a cube of side `a=0.1m` placed such that its six faces are given by equations `x=0,x=+a,y=0,y=+a,z=0` and `z=+a` placed in electric field given by `vec E=x^(2)+yhat j` N /C. If the electric flux crossing out of the cube in the unit of `10^(-4)Nm^(2)/C` is `10+x` find `x`