Step-by-step explanation:
Draw lines from one vertex to the other vertices, splitting the polygon into triangles. If the polygon has n sides, there will be n−2 triangles. Each triangle's angles add up to 180°. So the sum of all the interior angles is:
S = (n−2) 180°
1. (5 + 4) x 2 + 6 - (2 x 2) - 1
2. 9 x 2 + 6 - 4 - 1
3. 18 + 6 - 4 - 1
4. 24 - 4 - 1
5. 20 - 1
6. 19
THE first option is correct
To find the difference between these numbers you need to subtract 8.3 - 3.9
and that equals 4.4<span />