The sum of the three angles of a triangle is $\ldots \ldots \ldots$ (in $^o$)

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 $^{\circ}$)

State whether the following statement is true or false:
$(1)$ In $\Delta PQR$,$\angle P = \angle Q = 95^{\circ}$ is possible.

$\angle A$ and $\angle B$ are complementary angles. If $\angle A = \angle B - 20^{\circ}$,then find $\angle A$ and $\angle B$.

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

Two adjacent angles are equal. Is it necessary that each of these angles will be a right angle? Justify your answer.