P$\mathrm{.}1.(30$ points$)$ set $F_{AB}=250N$&$F_{AC}=400N$

a$)$ Determine the length of $AB$&$AC.$

b$)$ Determine the angle $$ between $AB$ and $AC.$

c$)$ Express the force vec$(F_{AB})$ and vec$(F_{AC})$ in Cartesian Vector notation.

d$)$ For the resultant force

e$)$ Determine the moment of force FAB about point C

I need part e the most