16. An electron has velocity v = (32 i + 40 j) km/s as it enters a uniform magnetic field B = (60 i) μT. (A) The radius of the helical path taken by the electron is 0.38 m. (B) The pitch of that path is 1.9 m. (C) The period of the revolution is 60 μs. (D) To an observer looking into the magnetic field region from the entrance point of the electron, the electron spirals counterclockwise as it moves. (E) The magnetic force points in the +k direction.