A large disk-shaped plate of plastic of radius 2 m has been rubbed all over with wool, and has a charge of -5 x 10 * coulombs distributed uniformly charge d plate over its surface. A solenoid, 2 m long, and composed of 3000 turns of wire, is located 0.5 cm from the charged plate. At a particular instant a proton is inside the solenoid, traveling along the x axis at a speed of 3 x 10# m/s in the -x direction. (a) How much current must be run through the solenoid to keep the proton from being deflected toward the charged disk? Z (b) What is the direction of the current that must run through the solenoid solenoid