选择题
2013 AMC 8 Problem 20: Rectangle in Semicircle
A 1×2 rectangle is inscribed in a semicircle with the longer side on the diameter. What is the area of the semicircle?
2013年AMC 8题20：半圆长方形
一个 1×2 的矩形内接于一个半圆，长边在直径上。半圆的面积是多少
A.
π/2
B.
2π/3
C.
π
D.
4π/3
E.
5π/3