如果数据来自不同的总体而画出的质量统计直方图的形状为（）型。
A、孤岛
B、平顶
C、双峰
D、偏峰
参考答案：C
—Was it there _______ you were away to see your friend off?
—I’m not sure . But when I got back, it was gone.
A．that
B．which
C．where
D．while
下面哪些LSA的洪泛范围只在单个区域？（）
A.Router LSA
B.Netwok LSA
C.Summary LSA
D.ASExternal LSA
