I need some help with the following questions concerning area and perimeter:

1. Calculate the area of a regular hexagon with a side length of 10 cm.

Would I use A triangle=0.5 X 10 X 5 and then multiply that again by 6?

2. Calculate the area and perimeter of the following segments:

a. A segment with a diameter of 20 cm.

b. A segment, when it is attached to a right angled triangle which has two side lengths of 12 cm.

3. Calculate the area and perimeter of one part of the yin-yangsymbol(so, I guess just the yin part).

Thank you! Please reply when you can, as soon as possible if possible!