An angle has a measure equal to $\frac{5}{4}$ of the measure of its complementary angle. Find the measure of that angle. (in $^o$)

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

$\angle ACD$ is an exterior angle of $\Delta ABC$ and the bisector of $\angle A$ intersects $BC$ at $E$. Prove that $\angle ABC + \angle ACD = 2 \angle AEC$.

If one of the two angles of a linear pair has measure $x^{\circ},$ then the other angle has measure of $\ldots \ldots . .$

How many triangles can be drawn having its angles as $53^{\circ}, 64^{\circ}$ and $63^{\circ}$? Give reason for your answer.