For stairs spanning l metres longitudinally between supports at the bottom and top of a flight carrying a load w per unit horizontal area, the maximum bending moment per metre width, is_______________?
For stairs spanning l metres longitudinally between supports at the bottom and top of a flight carrying a load w per unit horizontal area, the maximum bending moment per metre width, is_______________?
A. wl²/4
B. wl²/8
C. wl²/12
D. wl²/16