Answer: The formula is shown in the explanation
28.3
12.6
50.3
153.9
452.4
9.62
452.4
490.9
63.6
153.9
1520.5
2463
explanation: the formula for the area of a circle is pie radius squared. if you took the radius off all of these, then plugged it in your calculator then you would get the answer. if you need show your work, just look for the radius off of the problems and rewrite the formula but replace the R with the actual radius in the problem