Help

3.Two straight wires carrying the same current i are at two adjacent corners of a square with the side a. First wire carries current into the plane of the page and the second -out of the page. a) Find the net magnetic field at point P at the center of the side CD of the square. b) A proton is moving in the magnetic field due to the wires at the velocity v in the direction of the +x -axis. Find the magnitude and direction of the magnetic force on the proton at the instance when the proton is at point P. Express your answer in terms of e, a, and i. a B P A D