设有钢筋混凝土构造柱的抗震多层砖房,一般情况下,构造柱的最小截面尺寸应为()mm。
A.200x180
B.200x200
C.240x180
D.240x200
参考答案:C
调查某地25岁健康男子144人的身高、体重,算得身高的均数与标准差分别为170.1cm与4.9cm,体重的均数与标准差分别为54.0kg与5.1kg。据此资料。 估计该地95%的25岁健康男子身高(cm)不高于()
A.170.1+2.58×4.9
B.170.1+1.96×4.9
C.170.1+1.64×4.9
D.170.1+4.9
E.170.1+4.9/144
My parents often ask me _____ too much time _____ computer games. [ ]
A. not to spend; playing
B. not to spend; to play
C. to not spend; play