The supporting structure of the billboard is attached to the ground by a pin at B, and its rear leg rests on the ground at A. Friction may be neglected. Point G is the center of gravity of the billboard and structure, which together weigh 2800 lb. To prevent tipping over in high winds, a 2370-lb weight is placed on the structure near A, as shown.
(a) Compute the magnitudes of the reactions at A and B if the wind load on the billboard is q = 120 lb/ft.
(b) Find the smallest wind load q that would cause the structure to tip over.