11. Two vectors a and b, have a common starting point with an angle of 150 between them. Vector a = 5 and b = 7. Calculate a + b. (make sure to write the magnitude and direction) (10 points)10. Given two vectors a = (-1, -2, 1)and b = (3, -1, 1) does c = (-9, -4, 1) lie on the plane determined by a and b. (5 points)5. Find the unit vector perpendicular to both a = 37 - 2/ + k and b = 21 - j + 5k. (spo 6. If a and b are unit vectors and la + b| = v3 find (a - 2b) . (2a + 3b). (5 points)1. Determine the angle to the nearest degree between a = (2, 3,5)and b = (1, 2, -2).