4) A truss is a structural type characterized by: a) beams connected with hinges; b) beams rigidly connected to each other; c) beams connected anyhow, not loaded transversally to their axis. 5) With the Jourawski law the shearing stress components due to shear in a section: a) are constant along the direction orthogonal to the thickness of the cross section; b) vary linearly along the thickness of the cross section; c) are constant along the thickness of the cross section. 6) If the shear force is not applied on the centre of shear of the cross section then: a) the section is subject to bending moment in addition; b) the section is subject to torque in addition; c) the section is subject to pure shear.