..6 GO A proton moves through a uniform magnetic field given by B = (10i - 20j + 30k ) mT. At time ,, the proton has a velocity given by v = vxi + vyj + (2.0 km /s)k and the magnetic force on the proton is FB = (4.0 x 10-27 N)i + (2.0 x 10-27 N)j. At that instant, what are (a) Ux and (b) vy