The rule for regular polygons are very easy. The number of reflectional symmetries is same as the number of sides. Regular polygons have all sides the same length and all angles same. Reflection symmetry means that you can fold the shape along that line and it will match up.
For this question, we want the number of reflectional symmetries of a regular decagon. Decagon is a 10 sided figure. Hence, the number of reflectional symmetries is 10.
There are 5 symmetry lines from one vertex to opposite vertex and 5 more symmetry lines form midpoint of one side to midpoint of opposite side.
ANSWER: 10
Answer:

Step-by-step explanation:
A right angled triangle is given to us and we would like to find out the value of sin(A) .
From the triangle we can see that the measure of angle BAC is 30° . Therefore ,

On using sin both sides ,

As we know that the value of sin30° = 1/2. So;

Simplify by converting it into decimal ,

<u>Hence</u><u> </u><u>option</u><u> </u><u>B</u><u> </u><u>is</u><u> </u><u>correct</u><u> </u><u>.</u>
And we are done!
3 I think lol
- Samuel
Though, I’m not sure