单开道岔和对称（双开）道岔，交叉点位置横向位置允许偏差限界值是：（）。
A、20mm
B、30mm
C、50mm
D、80mm
参考答案：C
When they heard the ___________ news，they got very ___________．
A．frustrating, frustrated
B．frustrated, frustrated
C．frustrated, frustrating
D．frustrating, frustrating
( )不是长期偿债能力分析的指标。
A．资产负债率
B．负债与有形净资产比率
C．利息保障倍数
D．流动比率
