1. Three small spherical charges lie on a circle with radius 20.0 cm. The first sphere has a charge +20.0 nC and lies at 40 degrees counter clockwise (CCW) relative to +x axis. The second has charge +10.0 nC and lies at 140 degrees CCW to the +x axis; the third charge -30.0 nC lies at 280 degrees CCW to the +x axis. a. (5 points) Draw a physics diagram of the problem. Be sure to draw the field vector for each charge and the total field, at the center of the circle. b. (20 points) Find the electric field vector (in component form) for each charge at the center of the circle. Then compute the total electric field vector at the origin. 2. Find the unit vector with the same direction as the total electric field found in Problem 1. a. (5 points) Draw a physics diagram of the problem. b. (20 points) Express the unit vector in component form.