Consider the beam shown in the figure (not to scale), on a hinge support at end A and a roller support at end B. The beam has a constant flexural rigidity, and is subjected to the external moments of magnitude M at one-third spans, as shown in the figure. Which of the following statements is/are TRUE?

The infinitesimal element shown in the figure (not to scale) represents the state of stress at a point in a body. What is the magnitude of the maximum principal stress (in N/mm2, in integer) at the point? ________

The cross-section of a girder is shown in the figure (not to scale). The section is symmetric about a vertical axis (Y - Y). The moment of inertia of the section about the horizontal axis (X - X) passing through the centroid is _______ cm4 (round off to nearest integer). 

Consider the following three structures : 

Structure I : Beam with hinge support at A, roller at C, guided roller at E, and internal hinges at B and D

Structure II : Pin-jointed truss, with hinge support at A, and rollers at B and D

Structure III : Pin-jointed truss, with hinge support at A and roller at C

Which of the following statements is/are TRUE?