Q$3$: A pencil is pulled upward by a vertical force of F while three wires keep the pencil statics.

$($a$)$ Find $\frac{?}{{?}_{A}CO}\frac{,}{{?}_A}DO\frac{,}{{?}_A}BO\frac{,}{{?}_D}OE\frac{,}{{?}_B}OF$

$($b$)$ Write down the equation of force for the pencil along z direction

$($c$)$ Write down the equation of force for the pencil along x direction

$($d$)$ Write down the equation of force for the pencil along $y$ direction