Use the correct formula to find the area of a circle if the diameter is 21 mi. Round to the nearest hundredths place. Use 3.14 for π.

A. 65.94 mi.2

B. 346.19 mi.2

C. 1,384.74 mi.2

D. 131.88 mi.2

1 answer

The correct formula to find the area of a circle is: A = πr^2, where r is the radius of the circle.

We are given the diameter, which is 21 mi. The radius is half the diameter, so:

r = 21/2 = 10.5 mi

Now we can use the formula and substitute in the values:

A = 3.14 * 10.5^2 = 346.185 mi.2

Rounding to the nearest hundredths place, we get:

A ≈ 346.19 mi.2

Therefore, the answer is B. 346.19 mi.2.