Answer: A. 346.19 square feet
Explanation:
We know that , the formula to find the area of the circle is given by :-
, where r is the radius. (1)
Given : A contractor has been hired to install flooring for a bandstand in the shape of a circle that is 21 feet across.
That mean , the diameter of the circle = 21 feet
Then radius = half of diameter =

Now, the area of the bandstand :-
[using (1)]
Put
, we gte
Hence, the 346.19 square feet flooring will be required .