The mobile crane has a weight of 120000 lb and center of gravity at G1; the boom has a wei...

The mobile crane has a weight of 120000 lb and center of gravity at G1; the boom has a weight of 30000 lb and center of gravity at G2. Determine the smallest angle of tilt θ of the boom, without causing the crane to overturn if the suspended load is W = 40000 lb. Neglect the thickness of the tracks at A and B.