[单选题]()爆炸不属于化学爆炸。
A.炸药
B.可燃气体
C.粉尘
D.液化气钢瓶

右室双出口的概念下列何者不正确 ( )
 

One thing almost everyone is agreed on, including Americans, is that they place a very high valuation upon success. Success does not necessarily mean material rewards, but recognition of some sort preferably measurable. If a boy turns out to be a preacher (传道者) instead of a businessman, that’s all right. But the bigger his church is, the more successful he is judged to be.
A good many things contributed to this accent on success. There was the Puritan(清教徒的) belief in the virtue of work, both for its own sake and because the rewards it brought were regarded as signs of God’s love. There was the richness of opportunity in a land waiting to be settled. There was the lack of a settled society with fixed ranks and classes, so that a man was certain to rise through achievement.
There was the determination of an immigrant to gain in the new world what had been denied to him in the old, and on tile part of his children an urge to throw off the immigran
A. The Puritan belief in the virtue of work.
B. Determination to deny the values of the new world.
C. Lack of fixed social ranks and classes.
D. Richness of opportunities in the new world.