Which of the following statements is true about the congruence of triangles?

Shown below is a triangle drawn by a student. In the triangle below, $AB=BC\ne AC$. $D, E,$ and $F$ are the midpoints of their respective sides.

Which of the following lines divide $∆ABC$ into two congruent triangles?

In the parallelogram, $ABCD$, $O$ is the midpoint of $AC$ and $BD$.

Which of the following is not true?

Seema drew two congruent triangles, $∆ABC$ and $∆PQR$. The triangles along with a few measurements of angles and sides are given below.

What is the measure of $\angle PQR$?

Manu drew two straight lines bisecting each other at $O$. 

Which of the following congruence rules helps Manu prove that the triangles, $∆BOC,$ and $∆AOD$ are congruent?

Shown below is part of a window grill. $\angle COA=40°$, $OA=OC$, $BC\perp OC,$ and $BA\perp OA$.

The measure of angle, $\angle OBC$ is _____ $°$

Ram drew a right-angle triangle $∆ABC$ such that, $AB=AC$. Then he joined $AD$ such that, $AD\perp BC$.

He asserted, "The base angles, $\angle ACB=\angle ABC$" with the reason that, "$∆ACD\cong ∆DBA$

Which of the following statements is correct?

In the given $∆ABC$, $AB=AC$. $D$ and $E$ are the midpoints of the respective sides. 

If $BE=7 \mathrm{cm}$, then which of these lengths is also $7 \mathrm{cm}$?

Shown below is the rectangle drawn by Sriram. The diagonals of a rectangle are equal and they bisect each other. 

Sriram wants to prove if the given rectangle $ABCD$ can be proved to be a square. Which of this information is the necessary and sufficient condition to prove the same?