Consider two shafts in torsion, each of the same material, length, and cross-sectional area. One shaft has

Question:

Consider two shafts in torsion, each of the same material, length, and cross-sectional area. One shaft has a solid square cross section and the other shaft has a solid circular section.
(a) Which shaft has the greater maximum shear stress and by what percentage?
(b) Which shaft has the greater angular twist θ and by what percentage?