Answer: 346.19cm²
Explanation:
π= 3.14
Divide 21 (the diameter) by 2 to get the radius( it 's half of the diameter). so the radius is 10.5
Area= πr²
= 3.14x10.5x10.5
= 346.185
So next round up the value you got to the nearest tenth, so when u round up to the nearest tenth you get 346.19