Choose Layers > Load Combinations > Ultimate LC: 1.5D + 1.5L > Mx Plan.
The Mx contours should be visible.
Turn on Snap Orthogonal ()
Click the Selected Plot Distribution tool ().
Click first at grid intersection B-3, and then click at grid intersection D-3.
This shows the bending moment shape along the line you have drawn.
While pressing the <Shift> key, click at grid intersection B-1, and then click at grid intersection B-3.
This shows how Mx varies across the panel, and highlights the different column and middle strip moments.
See "Section distribution plots" for more information.
Ultimate LC: 1.5D + 1.5L Mx Plan showing use of Plot Distribution tool.