Find the area of a circle whose radius is 7 mm

The area of a circle is PiR^2, or Pi x R x R.
Pi is normally used as 3.14, as there is no end to it's decimal.
Since the radius is 7, we need to multiply the radius by itself and then by 3.14.
7 x 7 = 49.
49 x 3.14 = 153.86mm, or 153.9mm if rounded to the decimal place.
153.86mm^2 is your answer.
I hope this helps!

It is 49 pi mm or 153.86

Letter b hope it