Let a=(1,5,−1)a=(1,5,−1), b=(−3,6,−5)b=(−3,6,−5), c=(0,4,−9)c=(0,4,−9), and d=(4,3,−5)d=(4,3,−5). find the area of the parallelogram determined by these four points, the area of the triangle abcabc, and the area of the triangle abdabd.
