9. What is the area of a circle with radius 2 ?

Step 1 ：The problem is asking for the area of a circle with a radius of 2.

Step 2 ：The formula for the area of a circle is \(\pi r^2\), where \(r\) is the radius of the circle.

Step 3 ：Substitute 2 in place of \(r\) in the formula.

Step 4 ：Calculate the area: \(\pi (2)^2 = 12.566370614359172\).

Step 5 ：\(\boxed{12.566370614359172}\) is the final answer.