b$)$ A propped beam is $6\mathrm{.}0m$ long and supports an unfactored load of $47kN$ as shown in Figure $1.$ Assuming that the yield stress $f_y=460\frac{N}{m}{m}^2$ and a load factor $=1\mathrm{.}7,$ use Static method to determine the required plastic moment of resistance $M_p$ and plastic section modulus $)=(47kN$