Find the area of the shaded figure

Two drunks are walking along. One drunk says to the other, "What a beautiful night. Look at that moon!"

The other drunk stops and looks at his drunk friend. "You are wrong. That's not the moon; that's the sun!"

Both continued arguing for awhile when they came upon another drunk walking along. So they stopped him and said, "Sir, could you please help settle our argument? Tell us what that thing is up in the sky that's shining. Is it the moon or the sun?"

The third drunk look at the sky and then looked at them and said, "Sorry, I don't live around here."