Cranes, such as this one that is removing the crane that was involved in the brick refacing of krannert center, are comprised of truss-like structures to achive high strength and low weight. let us model the illustrated crane boom as a planar truss that is subjected to the tension load t . given the following: t= 750 kn l=3 m θ=5 degrees α=20 degrees determine force fab in kn in the blue member ab.