1. Given a = [8, -6, 4], b = [-2, 1, -3] and c = [7, 6, -2], find a) b . c b) axc c) 0, the angle between a and c d) projab e) Are the vectors a, b and c coplanar? Show your answer algebraically. 2. Determine the area of AABC with vertices A(2, - 1, 4), B(3, 1, - 1), and C (1, 0, 2). 3. If u and u are collinear and the magnitude of u is 7 times the magnitude of v, write an expression that represents the sum of u and