硬质物品不得使用特快专递邮件专用封套封装。
参考答案：对
Our meeting room is ______ theirs.
A．three times as bigger as
B．bigger than three times
C．three times as the size of
D．three times the size of
有序样本中，x(1)，是样本中的最______观测值，x(n)是样本中的最______观测值。( )
A．小；大
B．大；小
C．中间；边沿
D．边沿；中间
