The given figure has two concentric circles with centre $\mathrm{O}$. Answer the following:

Name three diameters.

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The given figure has two concentric circles with centre $\mathrm{O}$. Answer the following:

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 Write four equal line segments.

The given figure has two concentric circles with centre $\mathrm{O}$.

The region represented by $\mathrm{SOU}$ is called as a ........?

The given figure has two concentric circles with centre $\mathrm{O}$. What is represented by the region $\mathrm{STV}$?

Identify the arc. Write major/minor. 

Is the given arc minor or major?

Find the number of triangles in the given figure.

Find the number of squares in the given figure.

Classify the following curve as Open curve or Closed curve.