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问题 单项选择题

在原子吸收光谱法的理论中，以谱线峰值吸收量替代积分吸收测量的关键条件是()

A、光谱辐射的特征谱线与原吸收谱线比较，只要中心频率一样，半峰宽大小都没影响

B、光谱辐射的特征谱线与原吸收谱线比较，中心频率和半峰宽均为一样

C、光谱辐射的特征谱线与原吸收谱线比较，中心频率一样，而半峰宽要较大

D、光谱辐射的特征谱线与原吸收谱线比较，中心频率一样，而半峰宽要小得多

答案

参考答案：D

单项选择题

下列( )不是项目法人应具有的业务技能。

A．(A) 具有用系统工程管理建设项目的技能

B．(B) 具有编制招标文件和评标定标的技能

C．(C) 具有审查勘察设计文件的技能

D．(D) 具有签订符合国家有关规定的承包合同的技能
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单项选择题

I got a job teaching special education at a school in Coachella, California, a desert town about 170 miles from home. It was no (1) job. Street gangs (2) around the school after dark."Be careful," Dad warned me during one of my frequent weekend (3) home. He was concerned about my living (4) , but I needed to be on my own.One evening, I stayed after school to rearrange my classroom. (5) , I turned out the light and closed the door. Then I (6) toward the gate. It was (7) ! I looked around. Everyone had gone home.After (8) all the exits, I found just enough (9) to squeeze under a gate in the back of the school. Then I walked toward my car, parked in a field behind the building.Suddenly I heard voices. I (10) around and saw at least eight boys following me. (11) my pace, I reached into my shoulder bag to get my key. I (12) all over the inside of my handbag. But the key wasn’t (13) ! Dear Lord, please help me, I prayed (14) . Suddenly, my fingers touched a loose key in my purse. I didn’t even know if it was for my car, but I took it out and (15) it. It worked!I opened the door, slid in and locked it—just (16) the teenagers surrounded the car. Trembling , I started the engine and (17) away. When I returned to my apartment, the phone was ringing. It was my Dad. I didn’t tell him about my experience; I didn’t want to (18) him. "Oh, I forgot to tell you!" He said, "I had a(n) (19) car key made and slipped it into your purse—just (20) you ever need it.

第（14）空应选择（）

A．loudly

B．nervously

C．carefully

D．silently
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