$($i$)$ Five forces $F_1=(3(N),30),F_2=(1(N),180),F_3=(3\mathrm{.}5(N),250),F_4=(1(N),108),F_5=(2(N),270)$ act at point $O.$ Find the resultant and its direction

$($b$)$ A bullet of mass $0\mathrm{.}010$ kg is shot at a speed of $30\frac{m}{s}$ towards a $5$ kg stationary block. The bullet becomes embedded in the block and the two fly off together. Find the speed with which they fly off.

$($a$)$ A projectile is fired horizontally from a gun that is $20$ m above flat ground, emerging from the gun with a speed of $25\frac{m}{s}.$ At whut horizontal distance from the firing point does it strike the ground?

$($b$)$ A force of $50$ N is used to push a box through a distance $2\mathrm{.}4$ m $.$ A work of $451$ was dane on the box is$.$ Find direction of the force.

$($i$)$ What is the direction of the force?

$($ii$)$ Find the mass of the box if the velocity is $2\frac{m}{s}$