Directions: Question numbers 12 and 13 are based on the following paragraph. A current loop ABCD is held fixed on the plane of the paper as shown in the figure. The arcs BC (radius =b ) and DA (radius =a) of the loop are joined by two straight wires AB and CD. A steady current I is flowing in the loop. Angle made by AB and CD at the origin O is 30∘. Another straight thin wire with steady current l1 flowing out of the plane of the paper is kept at the origin. 