I really need help with these practice questions pleasee . Could you do them on a piece of paper so I can better understand them.

11. Given u =(2, 4, -3), v=(3, -1, 7), and w = (1, 0, -2), find a) 3u - 4V IMZ + Al (9 A . n (5 du x w e) u . (v x w) () (ux v ) x w 12. [al = 5, and [b| = 8, and the angle formed by a and b is 55. Determine |4a + b|. Round your answer to 2 d.p.13. Determine the value(s) of k such that the angle between the vectors a = (1, 1, k) and b = (1, 0, 1) is 45. 14. Determine the value(s) of x such that the area of the parallelogram formed by the vectors a = (x + 1, 1, -2) and b = (x, 3,0) is V41. 15. An airplane is flying at 600 km/h in the direction S48W. The wind is 80 km/h from the east. Find the resultant ground speed and direction of the airplane. Round your answers to 2 decimal places. Make sure you provide a diagram in your solution