a.
b.
c.
[tex]\begin{gathered} r^2=400^2+300^2 \\ r^2=160000+90000 \\ r=\sqrt[]{250000} \\ r=\text{ }500\text{ N} \end{gathered}[/tex]
d.
[tex]\begin{gathered} \tan x=\frac{400}{300} \\ x=\tan ^{-1}1.33333333333 \\ x=53.1301023473 \\ x\approx53^{\circ} \end{gathered}[/tex]
