problem 2. figure below shows two current-carrying loops with i1 = 4.00 a clockwise and i2 = 8.00 a counterclockwise, placed with their centers at the origin of the xy-plane. o = 4107 t·m/a. (a) if r1= 10.0 cm and r2 = 16.0 cm, what are the magnitude and direction of the magnetic field due to the two loops at the origin? write your answer in unit vector notation. (b) if r1 is held constant at 10.0 cm, what would r2 have to be for the total magnetic field at the origin to be 0?