当物价不断上涨时，采用后进先出法对存货进行计价，遵循的是（）原则。
A.收入与费用配比
B.历史成本
C.谨慎性
D.权责发生制
参考答案：C
I___ Beijing in a few days. Do you know when the earliest plane ____ ?
A．leaves; takes off
B．am leaving; takes off
C．leave; is taking off
D．am leaving; is taking off
《铁路信号维护规则》对ZD6电动转辙机动接点在静接点片内的接触深度有何要求？
