l4] l3] l3] 6. Determine if the vectors ('1' = [1,5, 3], E = [2, 4, 7], and E = [10, 7, 1] are coplanar. 7. Given a = [4,7,1] and B = [3.15]: a) Calculate the angle between ('1' and 3. b) If E = [3, 4, I], find I so that {1' and E are perpendicular