If the measure of an acute angle is $x^{\circ}$,find the difference of the measure of its supplementary angle and complementary angle. (in $^{\circ}$)

In the figure,$\angle 1 = 60^{\circ}$ and $\angle 6 = 120^{\circ}$. Show that the lines $m$ and $n$ are parallel.

Let $OA, OB, OC$ and $OD$ be rays in the anticlockwise direction such that $\angle AOB = 100^{\circ}, \angle COD = 100^{\circ}, \angle BOC = 82^{\circ}$ and $\angle AOD = 78^{\circ}$. Is it true to say that $AOC$ and $BOD$ are lines?

In the figure,if $AB \parallel CD \parallel EF$,$PQ \parallel RS$,$\angle RQD = 25^{\circ}$ and $\angle CQP = 60^{\circ}$,then $\angle QRS$ is equal to: (in $^{\circ}$)

An angle which is greater than $180^{\circ}$ but less than $360^{\circ}$ is called a $\ldots \ldots \ldots .$.

$\angle ACD$ is an exterior angle of $\Delta ABC$. The bisector of $\angle ABC$ and exterior $\angle ACD$ intersect each other at point $E$. Prove that,$\angle BEC = \frac{1}{2} \angle BAC$.