$2.$Taking $L=8m,h=4m,W1=0,W2=0,W3=0,P1$ and $P2$ are the values given in table. By portal method determine: the bending moment at points $($A$1,$ A$2,$ A$3,$ B$1,$ B$2,$ B$3,$ D$1,$ D$2,$ C$2,$ C$4,$ C$6$ and C$8)$; $-$the shear forces at points $($A$1,$ A$2,$ A$3,$ B$1,$ B$2,$ B$3,$ D$1$ and D$2.)$ and all reaction forces at points A$1,$ A$2$ and A$3.$

$\backslash$table$[[$P$1,$N$,$P$2,$N$],[640,1920]]$