need help on these questions

4. Suppose that two distinct lines (AB) and (CD) are parrallel. Which of the following properties must be true? Choose all valid answers. A. 2 . LABC = 2 . LBCD; B. AC = BD; C. KABC = LBCD; D. AABC ~ ACBD. 5. Let X be a point on the external bisector of ZABC. If LABC = -, what are possible values for XX BC"? Choose all possible answers. A. B. C. 3TT 7 D. 7 6. Suppose that D is the point of intersection of the bisector of ZBAC with the side [BC] of a triangle ABC. If AB = 6, AC = 8, and BD = 3, find CD. A. 7; B. 6; C. 5; D. 4