16. In the diagram of ?ABC, points D and E are on \overline{AB} and \overline{CB}, respectively, such that \overline{AC} \parallel \overline{DE}.
If AD = 24, DB = 12, and DE = 4, what is the length of AC?
1) 8
2) 12
3) 16
4) 72
17. In ?CED as shown below, points A and B are located on sides \overline{CE} and \overline{ED}, respectively. Line
segment AB is drawn such that AE = 3.75, AC = 5, EB = 4.5, and BD = 6.
Explain why \overline{AB} is parallel to \overline{CD}.