Question

Math homework help wanted

Answer 1

Answer:

C. $2\pi$

Step-by-step explanation:

Central angle $( \theta) = \frac{\pi}{2} = 90\degree$

Radius (r) = 4

$l(\widehat{EF}) = \frac{ \theta}{360 \degree} \times 2\pi \: r \\ \\ = \frac{90 \degree}{360 \degree} \times 2\pi(4) \\ \\ = \frac{1}{4} \times 2\pi(4) \\ \\ l(\widehat{EF}) = 2\pi$