A parallel plate capacitor is made of two circular plates separated by a distance of 5 mm with a dielectric of dielectric constant 22 between them. When the electric field in the dielectric is 3 x 104 V/m, the charge density of the positive plate will be close to
(a) 6 x 10-7 C/m2
(b) 3 x 10-7 C/m2
(c) 3 x 104 C/m2
(d) 6 x 104 C/m2
