A uniform magnetic field points up out of a page for the bottom 3/4 of the page. A rectangular loop of wire in the same plane as the page carries a current of 2.5mA counterclockwise. The rectangle has widths of 10cm and lengths of 85cm and is positioned such that only one of the widths is within the magnetic field. An insulating spring constant of 10 N/M attached to the width at the top of the page is stretched .25m by the magnetic force. The lengths are parallel to the sides of the page. What is the magnetic field?