please solve

(13 marks) 50. Calculate the area of the triangle ABC where A is (-1, 2, 4), B is (1, -1, 2), and C is (2, 3, 4). (4 marks) 51. Calculate the volume of the parallelepiped defined by the vectors a = (2, -5, -1), b = (2, 0, -1), c = (-1, 0, 1). (4 marks) 52. a) Find the torque produced when a 50 N force is applied at a 30 angle to the horizontal at the end of a 30 cm wrench. What is the maximum torque that can be applied by the 50 N force on the wrench and how can this be achieved? (3 marks) b) While moving a couch 5 m across the room, you have to lift and drag it at the same time. You exert a force of 200 N at an angle of 70 to the floor as you drag the couch. How much work do you do moving the couch? (2 marks)