将带火星的木条插入一瓶无色气体中，木条剧烈燃烧，说明该气体是 [ ]
A．氮气
B．空气
C．氧气
D．二氧化碳
答案：C
由某地300名8岁正常男孩收缩压估计该地8岁正常男孩平均收缩压的95%可信区间，可选择的计算公式为（）
A.±1.96S
B.±2.58S
C.
D.
E.
-Some dinosaurs were the __________ of buildings.
-They were as __________ as buildings.
A. big, bigger
B. size, big
C. size, the biggest
±1.96S
