Question

the formula for the circumference of a circle is $c = 2pi r$. determine the circumferen
a. $100pi$ cm c. $20$ cm
b. $20pi$ cm d. $100$ cm

please select the best answer from the choices provided

a
b
c
d

Explanation:

Step1: Recall the formula

The formula for the circumference of a circle is \( C = 2\pi r \). Assuming the radius \( r = 10 \) cm (since the options suggest a radius that would lead to these results, for example, if \( r = 10 \), then \( C=2\pi\times10 = 20\pi \) cm).

Step2: Match with options

Option a is \( 100\pi \) (which would be if \( r = 50 \), not likely), option b is \( 20\pi \) (matches \( r = 10 \)), option c is 20 (no \( \pi \), incorrect), option d is 100 (no \( \pi \), incorrect).

Answer:

B. \( 20\pi \) cm