为了安全，设计与安装手压平刨刀轴规定，刨刀刃口伸出量不能超过刀轴外径( )mm。
A．1.1 B．1.3C．1.5 D．1.8
参考答案：A
—Why don’t you like winter in Beijing?
—Because it is winter in Guangzhou.
A．as cold as
B．much colder than
C．not so cold as
D．not colder than
判断强碱能对弱酸进行准确滴定的条件是( )。
A．C≥10-6(mol/
B．C/Ka≥500
C．C·Ka≥20Kw
D．C·Ka≥10-8
E．Ka1/Ka2≥104
