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【单选题】
1*75.某小学有大批的学生发生不明原因的腹污,为了寻找病因及流行的线素。通过第一步研究,提示大批学生的腹泻可能与饮用了某厂生产的饮料有关,下一步最好采取
A.
病例对照研究
B.
临床试验研究
C.
现况调查研究
D.
理论流行病学研究
E.
现场研究
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【单选题】27 以下关于旅游活动中溺水事故预防的说法中,不正确的是( )
A.
在旅游活动中,导游员要劝阻旅游者不要单独去偏僻或水清不明的地方游泳
B.
旅游团集体游泳时导游员应提醒旅游者在下水前要做好准备活动,以防抽筋
C.
导游员要提醒身体过度疲劳、过饱过饿的旅游者下水游泳时要特别注意安全问题
D.
组织水上漂流活动时,应安排旅游者穿好救生衣,安放好随身携带物品
【单选题】世界的统一性在于它的
A.
物质性
B.
存在性
C.
可知性
D.
运动性
【单选题】According to the conversation, what upsets the man?
A.
He doesn't know what color to choose.
B.
He has a broken rucksack.
C.
The gift he wants is out of stock.
D.
He doesn't know what gift will be useful.
【单选题】What aren't there that night according to the man?
A.
Films.
B.
Plays.
C.
Concerts.
【简答题】Choose the right answer according to what you hear. 1. Jim forgot _____. A. the lesson B. what the teacher said C. what his mother said 2. The story happened _____. A. in the evening B. in the afterno...
【单选题】What can you learn according to what you hear?
A.
The man doesn't like country music, but he has to learn.
B.
The man didn't know the bad news.
C.
The man didn't like John Denver.
【单选题】On what occasion will people notice the importance of nonverbal communication, according to the passage?
A.
When you have an interview with the manager.
B.
When you are .in a foreign country which language you can't understand.
C.
When you .are having a face to face communication.
D.
When you stand with somebody.
【单选题】what aren't there that night according to the man?
A.
Films.
B.
Plays.
C.
Concerts.
【单选题】What is the most important thing to overcome nervousness according to the woman?
A.
Don't be afraid of failing.
B.
Work very hard.
C.
Don't take it seriously.
【简答题】(14分)常见的一硝基甲苯有对硝基甲苯和邻硝基甲苯两种,均可用于合成各种染料。某探究小组利用下列反应和装置制备一硝基甲苯。 实验中可能用到的数据: 实验步骤:①按体积比1:3配制浓硫酸与浓硝酸混合物40 mL; ②在三颈瓶中加入15 mL(13g)甲苯,按图所示装好药品和其他仪器; ③向三颈瓶中加入混酸,并不断搅拌(磁力搅拌器已略去); ④控制温度约为50℃,反应大约10 min,三颈瓶底有大量淡...
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