Please show all work clearly thanks

Problem 2 The aurora is caused when electrons and protons, moving in the earth's magnetic field of 5x10-5T collide with molecules in the atmosphere causing them to glow. a) What is the radius of the circular orbit of an electron with speed 1x105m/s? (10pts) b) Describe in what ways, if any the orbit of the proton will differ from that of the electron in the same region (10pts)