Displacement vector vec$(A)$ points due east and has a magnitude of $1\mathrm{.}72km.$ Displacement vector vec$(B)$ points due north and has a magnitude

of $7\mathrm{.}73km.$ Displacement vector vec$(C)$ points due west and has a magnitude of $7\mathrm{.}24km.$ Displacement vector vec$(D)$ points due south and has

a magnitude of $1\mathrm{.}15km.$ Find $($a$)$ the magnitude of the resultant vector vec$(A)+$vec$(B)+$vec$(C)+$vec$(D),$ and $($b$)$ its direction as a positive angle relative

to due west.

$($a$)$ Number

Units

$($b$)$ Number

Units