(a) Define electric flux. Write its SI units.
(b) The electric field components due to a charge inside the cube of side 0.1 m are as shown :

`E_(x)=alpha x, ` where `alpha=500N//C-m`
`E_(y)=0, E_(z)=0`.
Calculate (i) the flux through the cube, and (ii) the charge inside the cube.