Q$4-$a$)$ A T section timber beam is connected together with nails at spacing of $80$ mm as shown in figure Q$4-$a$,$ knowing that the neutral axis of beam lies at distance $y=120\mathrm{.}45$ mm from top, and second moment of area $I=3\mathrm{.}7053{10}^{8}m{m}^4.$ The beam is subjected to a vertical shear force $V=20kN.$ Determine

i$.$ The shear force in each nail

$[5$ Marks$]$

ii$.$ The horizontal shear stress at $50$ mm from edge in upper plank.

$[5$ Marks$]$