Solution: (a) Simple curves are: (1), (2), (5), (6) and (7).

(b) Simple closed curves are: (1), (2), (5), (6) and (7).

(c) Polygons are: (1), (2) and (4).

(d) Convex polygon is: (2).

(e) Convex polygons are (1) and (4).

Solution:

Solution: The sum of measures of angles of a convex quadrilateral = 360° Yes, this property holds, even if the quadrilateral is not convex.

Solution: From the above table, we conclude that sum of the interior angles of polygon with n-sides = (n - 2) x 180°

(a) When n = 7

Substituting n = 7 in the above formula, we have Sum of interior angles of a polygon of 7 sides (i.e. when n = 7)

= (n - 2) x 180° = (7 - 2) x 180°

= 5 x 180°

= 900°

(b) When n = 8

Substituting n = 8 in the above formula, we have

Sum of interior angles of a polygon having 8 sides

= (n - 2) x 180° = (8 - 2) x 180°

= 6 x 180°

= 1080°

(c) When n = 10

Substituting n = 10 in the above formula, we have

Sum of interior angles of a polygon having 10 sides

= (n - 2) x 180° = (10 - 2) x 180°

= 8 x 180°

= 1440°

(d) When n = n

The sum of interior angles of a polygon having n-sides = (n - 2) x 180°