In a mass spectrometer the charged particles have to reach a common specific speed. To do so, they are accelerated with an electric field and then passed through a velocity selector consisting of a straight tube with a hole at the end. In that straight tube uniform electric and magnetic fields perpendicular to each other are maintained. In a certain device, the electric field is 300 V/m and points north, while the magnetic field is 25.0 mT and points upward. The particles, which we will assume are of the positive charge "Q", travel through various speeds east, where the hole is. Determine
a. the direction of the electric force
b. the direction of the magnetic force
c. which particles travel directly to the hole (discard the weight of the particles)