In a certain region, the earth's magnetic field has a magnitude of5.1 x 10-5 T and is directed north at an angle of57° below the horizontal. An electrically charged bullet isfired north and 11° above the horizontal, with a speed of 500m/s. The magnetic force on the bullet is 3.8 x10-10 N, directed due east. Determine the bullet'selectric charge, including its algebraic sign (+ or -).