A breeder wants to fence off his four-sided plot of flat land. He measures the first three sides, shown as A, B, and C in the figure, where A = 4.6 km,B = 2.73 km, and C = 2.81 km and then correctly calculates the length and orientation of the fourth side D.
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Part (a) What is the length of the vector D in kilometers?
Part (b) What is the orientation of the vector D, in degrees W of S?