深呼吸时两肺下缘可向上下各移动多大范围（）
A.不移动
B.0～1cm
C.2～3cm
D.3～4cm
E.4～5cm
参考答案：C
A．To question the opinion about pocket money.
B．To compare Stephens with other financial experts.
C．To explain that parents should. be strict when children are developing good habits about money.
D．To suggest that pocket money is useless in developing a child’s sense of responsibility.
当传动轴在运转过程中，发热温度升高时会降低轴的（），加快轴的磨损。
A、圆柱度
B、同轴度
C、硬度
D、钢度
