The radius of a circle is 7.31. How should the circle area be reported?

I'm not sure but it should be 7.31 times 2 times 3.14 or pi

7.31 x 2 x 3.14 = 45.9068

If you need to round to the nearest tenth it will be 45.9

If you need to round to the nearest hundredth it will be 45.91