阿司匹林抗拴作用的机制是( ) A．抑制磷脂酶A2，减少TXA2的生成 B．抑制脂

计算2a-3(a-b)的结果是[ ]

A．-a-3b

B．a-3b

C．a+3b

D．-a+3b

收购方式有（）。

A.以现金购买资产

B.用股票收购

C.以现金购买股票

D.承担债务式收购

Part 1

·You are a regional manager for an international company. You have been asked to go to a meeting at your company’s head office. You cannot go, so somebody else will go in your place. Write a letter to Eric Young who is organizing the meeting.
☆ Explaining why you cannot go.
☆ Saying who will go.
·Write 50-60 words.

The policeman asked the small girl _____.[ ]

A. why she was crying

B. why was she crying

C. why she is crying

D. why is she crying

简述燃煤发电厂的燃烧系统流程？