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Multiple Choice Identify the choice that best completes the statement or answers the question. 5. When simplified, u + 3u -2u equals a. 6u C . 0 b. 2u d. -2u 6. |u|= 3, | v|=2, and the angle between u and v (when placed tail-to-tail) is 450. Find |2u + 3v|. a. 11.09 C. 12 12 b. 12 d. 5 7. An airplane is flying at 450 km/h on a heading of 270. The wind is blowing at 75 km/h from a bearing of 180. Find the groundspeed (the magnitude of the ground velocity) of the airplane. a. 525 km/h b. C. 456.21 km/h 476.33 km/h 1. 375 km/h 8. If a = [1, 2] and b = [2, 7], find a + 2b. a. 3~10 C. [5, 16] b. [6, 18] d. 281 9. Which vector is collinear with [2, -3]? a. [2, -6] [-2, -3] C. [12, 18] d. [-4, 6] 10. A ship is on a heading of 050 at 30 knots. Write this velocity as a Cartesian vector. a. [22.98, 19.28] b. [19.28, 22.98] C. [30, 30] d. [50, 30] 1 1. If |a| = 3, b = 5, and the angle between a and b is 450, find a . b. a. 15 C . 15 b. 15 ~2 d. [3, 5]