8. Calculate the area of the parallelogram whose adjacent sides are: d = [6, 3, 2] and E = [1, 3, -1] [4] 9. The points A[1, 1, 1], B[2, 0,3], and C[3, 3, 4]. Show that this triangle is a right-angle triangle. [3] 10. Determine the following: a) Determine the vector equation of the plane that contains the following two lines L1: r = (2, 3, 5) + DB, 1, 5),teR [2] L2: 1" = (2, 3, 5) + s(0,4,3),SER b) Determine the corresponding Cartesian equation. [5]