3) In each part, determine whether u and v make an acute an- gle, an obtuse angle, or are orthogonal. (a) u=7i+3j+5k, v=8i+4j+2k (b) u=6i+j+3k, v=4i6k (c) u = 1,1,1, v = 1,0,0 (d) u = 4,1,6, v = 3,0,2 4) Does the triangle in 3-space with vertices (1,2,3), (2, 2, 0), and (3, 1, 4) have an obtuse angle? Justify your answer. 25) In each part, find the vector component of v along b and the vector component of v orthogonal to b. (a) v=2ij+3k, b=i+2j+2k (b) v = 4,1,7, b = 2,3,6 >>> Express the vector v as the sum of a vector parallel to b and a vector orthogonal to b. 26) (a) v=2i4j, b=i+j (b) v=3i+j2k, b=2ik (c) v=4i2j+6k, b=2i+j3k 27.) (a) v = 3,5, b = 1,1 (b) v = 2,1,6, b = 0,2,1 (c) v = 1,4,1, b = 3,2,5