Question 1: The area of the square is the product of the two sides. 24 times 24 is 576. Thus, the square is 576 square inches.
Question 2: (Answer is based off info received from comments)
The area of a circle is
, where r is the radius. The diameter you have given me is 20 inches. The radius is half the diameter; thus, the radius is 10.
They want us to approximate the area.
is approximately 3.14. If we use this value, we get 314 square inches.