QUESTION $1[25$ Marks$]$

a$)$ State the Principal of Transmissibility? given that the members used are $250$ mm thick. $[6+8$ marks$]$

Fig. $1$

c$)$ For Fig. $2,$ Draw the complete Free Body Diagram of the beam ABEC knowing that pulley D is a frictionless pulley and the mass of the load is $1750$ kg $.$

$[6$ marks$]$