Area of a Circle for ninth grade: Calculating parts of the circle

Calculate the area of the section painted red given that the area of the circle is 12.

8

Calculate the area of the section shaded in red given that the area of the circle is 36.

$2$

Calculate the area of the sector marked in red given that the area of the circle is 12.

$2$

Calculate the area of the sector shaded in red given that the area of the circle is 6.

$\frac{5}{6}$

Calculate the length of the arc marked in red given that the area of the circle is 24.

$10$

Calculate the area of the section marked in red given that the area of the circle is 18.

$13$