Quantities which are directly measurable in this lab are the accelerating voltage AV, radius of the electron's path r, and the magnetic field B. Using equations 1 and 2 write a formula which relates the radius of the electron's path r to other measurable quantities, and the ratio e/m. You should be able to write this equation in the form r = C where is a constant. Determine an expression for the constant C in terms of mea- sureable quantities and the charge to mass ratio e/m. Using the equation from question 2, explain how you could plot your data in such a way that you could determine e/m using the slope of a graph