In the structure shown P$1=28$ kN$,$ P$2=48$ kN$,$ and W $=8$ kN$/$m$.$ The pins at A$,$ B$,$ and D are to be made of steel having ultimate shearing stress equal to $370$ Mpa, and Link AB $($link thickness $=20$ mm$)$ is to be made of steel having ultimate normal stress equal to $520$ MPa. And given that factor of safety for shear stress will be $4\mathrm{.}5$ and for normal stress will be $5\mathrm{.}4.$ Given also that the allowable bearing stress is equal to $280$ Mpa, L$1=0\mathrm{.}4$ m$.$ Answer the questions in the table below: $($ALL PINS ARE IN DOUBLE SHEAR$)$