I need help with these 4 questions quickly, no explanation needed!!!

Question 1 (1 point) If a = (3, 2, 9) and b = (-4, 7, 1), find a . b. Question 2 (1 point) For which of the following conditions will the dot product of two vectors be zero? O ala. b=-9 a) The angle between them is 90". O b) a . b = 11 (b) The angle between them is 0' c) The angle between them is 180" Oca. b= 20 d) The vectors have the same magnitude. Oda . b = 12 Question 3 (1 point) If lal = 12 cm, jb) = 13 cm, and the angle between them when placed tail to tail is 35, find a . b. Oala . b - 57 Obla . b - 128 Oda . b = 11 Od) a . b = 24 Question 4 (1 point) The dot product represents: a) A vector parallel to both given vectors. ( b) The magnitude of the projection of one vector onto another. c The division of one vector by another. d) A vector perpendicular to both given vectors