Help anyone can help me do this question,I will mark brainlest.

Answer:
Solution given:
note=diameter=2*radius
1:
Area of circle =πr²=22/7*(21/2)²=346.5cm²
2:
radius (r)= 3 ½=7/2cm
Area of circle =πr²=22/7*(7/2)²=38.5cm²
3;
radius (r)=14/2=7cm
Area of circle =πr²=22/7*(7)²=154cm²
note:
π=3.14 or 22/7