Displacement vector A points due east and has a magnitude of 2.29 km. Displacement vector B points due north and has a magnitude of 8.82 km. Displacement vector C points due west and has a magnitude of 9.93 km. Displacement vector D points due south and has a magnitude of 2.93 km. Find (a) the magnitude of the resultant vector A+B+C+D , and (b) its direction as a positive angle relative to due west.