亚音速气流流过扩张形管道时,其()
A.速度增加,压力下降
B.速度减小,压力增加
C.速度减小,压力下降
D.速度增加,压力增加
参考答案:B
根据划线部分提问。
1、He often does his test in the lab.
2、Martin can answer all the questions.
3、Most of the plants will be dead because of no water.
4、Jack will leave for London by Easter Airlines Flight 664.
5、We listened to the weather report last night.
下列选项中属于教育的间接成本的是( )。
A.学费
B.书籍费
C.额外的吃、穿、住等费用
D.放弃目前工作继续学习而放弃的工资收入