How many transversals can be drawn for two distinct lines?

Fill in the Blanks : The number of transversals can be drawn to two distinct lines are____.

How many straight lines can be drawn by joining 15 distinct points on a circle ?

How many perpendicular lines can be drawn to a given line?

How many perpendicular lines can be draw to a given line ?

How many isomers can be drawn for pentane with molecular formula C_5 H_12 ? What are they? Draw their structures and mention their common names.

How many radii can we draw in a circle ?

A transversal line intersects two distinct lines in _____distinct points.