Part 4: Application [10 marks] 21. If u and u are collinear and the magnitude of u is 7 times the magnitude of v, write an expression that represents the sum of u and v. [2 marks] 22. Determine the area of AABC with vertices A(2, - 1, 4), B(3, 1, - 1), and C (1, 0, 2). [4 marks] 23. A ship is on a heading of 040 at 20 knots and a 2 knot current is flowing from 010. Determine the resultant velocity of the ship to 1 decimal place. [4 marks]