Answer:
8\pi units^{2}
Step-by-step explanation:
The shaded sector is half the area, because its divided in two parts by the diameter, which is in the middle. So, one way we could get the answer is finding the total area, then divide it by two, like this:
[tex]A=\pi r^{2} \\A=\pi (4)^{2} \\A=16\pi[/tex]
Then, the shaded sector is half:
[tex]A_{shaded}=\frac{A}{2}=\frac{16\pi}{2}=8\pi units^{2} [/tex]
Therefore, the correct answer is the second option.
