In unit$-$vector notation, what is the torque about the origin on a particle located at coordinates $(0,-8\mathrm{.}64m,2\mathrm{.}73m)$ due to $($a$)$ force $F$ with components $F_{1x}=1\mathrm{.}35N$ and $F_{1y}=F_{1z}=0,$ and $(b)$ force vec$(F{)}_2$ with components $F_{2x}=0,F_{2y}=4\mathrm{.}83N,F_{2z}=1\mathrm{.}56N?$

$($a$)$ Number hat$(i)$ widehat$(j)$

$$ widehat$(k)$ Units $$

$($b$)$ Number $$ hat$(i)+$ hat$(j)$

$$ widehat$(k)$ Units $$