活页账的优点是使用灵活,便于分工记账,但容易散失和被抽换。()
参考答案:对
104. What do you think _____ to her? She is very angry now.
A.did he do
B.he did
C.does he do
D.has he done
锅炉爆管的处理正确的是()。
A、开启过热器、蒸汽管道和分汽缺睥疏水阀
B、如因锅炉缺水,管壁过热而爆管时,应及时向锅炉给水,以维持水位正常.
C、炉管破裂不能保持水位时,应紧急停炉
D、应紧急停炉,并严禁向锅炉给水