(a) If a (6,-9,-1) and b = (-6,9,-3), find a x b. Enter the coordinates of axb (in order) into the answer box below, separated with a comma. (b) If a = -9j - k and b = -6i + 9j, find axb. Enter the coordinates of ax b (in order) into the answer box below, separated with a comma. (c) The figure below shows a vector a in the xy-plane and a vector b in the direction of k. Their lengths are lal 8 and lbl = 5. Find la x bl a