Identify the figure and mark the corresponding number as the answer

$1$ for simple curve $/$ $2$ for simple closed curve $/$ $3$ for convex polygon $/$ $4$ for concave polygon $/$ $5$ for None of these.

Classify the given figure on the basis of the following:
(i) Simple curve
(ii) Simple closed curve
(iii) polygon
(iv) Convex polygon
(v) Concave polygon

Classify the given figure on the basis of the following:
(i) Simple curve
(ii) Simple closed curve
(iii) polygon
(iv) Convex polygon
(v) Concave polygon

Classify the given figure on the basis of the following:
(i) Simple curve
(ii) Simple closed curve
(iii) polygon
(iv) Convex polygon
(v) Concave polygon

Classify the given figure on the basis of the following:
(i) Simple curve
(ii) Simple closed curve
(iii) polygon
(iv) Convex polygon
(v) Concave polygon

How many diagonals does a Convex quadrilateral have?

How many diagonals does the following figure have?

A regular hexagon.

How many diagonals does a triangle have?