A current of 2.0 A is flowing along the z-axis in the positive z direction from the origin to z=-2 m. Find the magnetic field (direction and magnitude) at the following three points of interest (x,y,z): P1 (1 m, 1 m, 0 m), P2 (2 m, 0 m, 3 m), P3 (1 m, 2 m, 2 m). Which field is the strongest? Why?