State if the following pairs of triangles in the figure are similar or not. Write the similarity criterion used by you for answering the question and also write the pairs of similar triangles in the symbolic form:

State whether the following pair of triangles is similar or not.

State whether the pair triangles are similar or not. Write the similarity criterion used by you for answering the question and also write the pair of similar triangles in the symbolic form.

In the following figure, $∆\mathrm{O}\mathrm{D}\mathrm{C}~∆\mathrm{O}\mathrm{B}\mathrm{A}, \mathrm{\angle }\mathrm{B}\mathrm{O}\mathrm{C}={125}^{\circ }$ and $\mathrm{\angle }\mathrm{C}\mathrm{D}\mathrm{O}={70}^{\circ }$. Find $\mathrm{\angle }\mathrm{D}\mathrm{O}\mathrm{C}, \mathrm{\angle }\mathrm{D}\mathrm{C}\mathrm{O}$ and $\mathrm{\angle }\mathrm{O}\mathrm{A}\mathrm{B}$.

In the figure given below $\frac{\mathrm{Q}\mathrm{R}}{\mathrm{Q}\mathrm{S}}=\frac{\mathrm{Q}\mathrm{T}}{\mathrm{P}\mathrm{R}}$ and $\angle 1=\angle 2$. Show that $△\mathrm{P}\mathrm{Q}\mathrm{S}~△\mathrm{T}\mathrm{Q}\mathrm{R}$.

In Fig. if $\mathrm{}∆\mathrm{}\mathrm{A}\mathrm{B}\mathrm{E}\cong ∆\mathrm{}\mathrm{A}\mathrm{C}\mathrm{D}$, show that $\mathrm{}∆\mathrm{}\mathrm{A}\mathrm{D}\mathrm{E}\mathrm{}~\mathrm{}∆\mathrm{}\mathrm{A}\mathrm{B}\mathrm{C}$.