A charged particle of mass 'm' and charge 'q' moving under the influence of uniform electric field $E\overrightarrow i$ and a uniform magnetic field $B\overrightarrow k$ follows a trajectory from point P to Q as shown in figure. The velocities at P and Q are respectively, $v\overrightarrow i$ and $- 2v\overrightarrow j$. Then which of the following statements (A, B, C, D) are the correct ? (Trajectory shown is schematic and not to scale) : (A) E =$${3 \over 4}\left( {{{m{v^2}} \over {qa}}} \right)$$(B) Rate of work done by the electric field at P is $${3 \over 4}\left( {{{m{v^3}} \over a}} \right)$$ (C) Rate of work done by both the fields at Q is zero (D) The difference between the magnitude of angular momentum of the particle at P and Q is 2mav.