Give another name for the line of symmetry in a circle.

Draw any $\Delta \mathrm{XYZ}.$ Take a point $\mathrm{O}$ in its interior. Draw a perpendicular from $\mathrm{O}$ to $\overline{\mathrm{XY}},\overline{\mathrm{YZ}}$ and $\overline{\mathrm{XZ}}$.

For the given figure, name two pairs of intersecting line segments.

For the given figure, name the type of quadrilateral $\mathrm{ABCD}$.

Name two right-angled triangles for the following figure.

Name two obtuse-angled triangles for the following figure.

Name the type of the following triangles:

$\mathrm{\Delta PQR}, \angle \mathrm{P}=40°, \angle \mathrm{Q}=60°, \angle \mathrm{R}=80°$

Name the type of the following triangle:

$\mathrm{\Delta DEF}, \angle \mathrm{D}=90°, \mathrm{DE}=\mathrm{DF}=5 \mathrm{cm}$

(Right angled triangle/Right angled isosceles triangle)