Group the given figures into three classes on the basis of their identical properties using each figure only once.

Select a figure from the options which will complete the given figure matrix.

Select a figure from the options which satisfies the same conditions of placement of dots as in the given figure.

In the given figure, if $\angle A=2\angle B$ and $\angle ACD=2\angle DCB$, then find the measure of $\angle DCB+\angle B$

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Which of the following options represents the value of $P$ shown on the number line?