In the following figure $OA$ and $OB$ are opposite rays. If $x=75°$, what is the value of $y$? 

In the following figure $OA$ and $OB$ are opposite rays. If $y=110°$, what is the value of $x$? 

In the following figure determine the value of $y$. 

In the following figure $m\parallel n$ and $\angle 1=65°$. Find $\angle 5 \text{and} \angle 8$. 

In the adjoining figure, $l_1\parallel l_2$. Find the measure of the angle marked $e$.

In the given figure, $AB\parallel DC$ and $AD\parallel BC$, and $AC$ is a diagonal. If $\angle BAC=35°$,$\angle CAD=40°$, $\angle ACB=x°$, and $\angle ACD=y°$, find the value of $x$ and $y$.

In the given figure, $AB\parallel CD$ and $CA$ has been produced to $E$ so that $\angle BAE=125°$.
If$\angle BAC=x°$, $\angle ABD=x°$, $\angle BDC=y°$ and $\angle ACD=z°$, find the values of $x$, $y$, $z$.

Suman has drawn figure $\left(\mathrm{i}\right)$ and Sneha has drawn figure $\left(\mathrm{ii}\right)$ as shown below. Both of them have marked line $l$ as the transversal. Who is wrong and why $?$

In the adjoining figure, $BOD$ is a straight line and $\angle AOB=x$. If $\angle COD$ is $3$ times of $\angle AOB$ and $\angle AOD$ is $4$ times of $\angle AOB$, then find $\angle BOC$.