15. A horizontal bars is an example of an intersecting lines.
16. An angle formed from the corner of a chalkboard is an acute angle
17. Points that are all in the same line is a noncollinear points.
18. An angle whose measure is 75 degrees is an obtuse angle.
19. Skew lines are three or more lines that have a common endpoint.
20. Line segment is longer than a line.​