1. [12 marks] a. Calculate the dot product of a = (1,2,3) and b = (-1,4,2). b. Calculate the dot product of a and b if the angle between them when placed tail to tail is 65, lal = 5 and |b| = 3. Round your answer to the nearest tenth. c. Given the vectors a = (-1,0,2) and b = (3,1,4), calculate the angle between them to the nearest degree. d. For which values of k are the vectors x = (k, -2, k) and y = (k, 4, -2) perpendicular