Question

The angle between two parallel lines is ___.

• A. $0^o$
• B. ${90}^o$
• C. ${360}^o$
• D. ${180}^o$

Answer 1

The correct option is D ${180}^o$

When a third line intersects two lines and if the interior angles are less than ${180}^o$, they meet at a point if extended. But if the interior angles are exactly ${180}^o$ the figure obtained is a pair of parallel lines. Hence, the angle between two parallel lines are ${180}^o$.