If $c$  is the velocity of light in free space, the correct statements about photon among the following are:

A. The energy of a photon is  $E=hv$ .

B. The velocity of a photon is c.

C. The momentum of a photon,  $p=\frac{hv}{c}$ .

D. In a photon-electron collision, both total energy and total momentum are conserved.

E. Photon possesses positive charge.

Choose the correct answer from the options given below:

Four metallic plates, each with a surface area A, are placed at a distance d from each other as shown in the figure. If points A and B is connected with a battery of emf V, then the charge on the plate a will be   

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