If two parallel lines are intersected by a transversal,then each pair of corresponding angles are...........

In the figure,$BA \parallel ED$ and $BC \parallel EF.$ Show that $\angle ABC + \angle DEF = 180^{\circ}.$

If two interior angles on the same side of a transversal intersecting two parallel lines are in the ratio $2:3,$ then the greater of the two angles is (in $^{\circ}$)

Two lines $l$ and $m$ are perpendicular to the same line $n$. Are $l$ and $m$ perpendicular to each other? Give reason for your answer.

In the figure,if $OP \parallel RS,$ $\angle OPQ = 110^{\circ}$ and $\angle QRS = 130^{\circ},$ then $\angle PQR$ is equal to: (in $^{\circ}$)

In the figure,find the values of $x$ and $y$ and then show that $AB \parallel CD$.