Question

determine if each statement is always, sometimes, or never true. 1. parallel lines are coplanar. 2. perpendicular lines are coplanar. 3. distance around an unmarked circle can be measured.

Explanation:

Step1: Recall parallel - lines definition

Parallel lines are defined as lines in the same plane (coplanar) that never intersect. So parallel lines are always coplanar.

Step2: Recall perpendicular - lines definition

Perpendicular lines are two lines that intersect at a right - angle. In a two - dimensional plane (the most common context), they are coplanar. In three - dimensional space, skew lines can be perpendicular (not in the same plane), but the basic definition of perpendicular lines in a plane makes them coplanar. So perpendicular lines are sometimes coplanar.

Step3: Analyze circle - measurement

The distance around a circle is the circumference. Without any markings or known information about the circle (such as radius or diameter), we cannot directly measure its circumference. So the distance around an unmarked circle can never be measured.

Answer:

1. Always
2. Sometimes
3. Never