试题与答案

干冰是固态的二氧化碳,在常温下易升华,如图所示是干冰升华时的情景,根据图中信息,

题型:填空题

题目:

干冰是固态的二氧化碳,在常温下易升华,如图所示是干冰升华时的情景,根据图中信息,从“物质性质

决定
体现
物质用途”这一角度分析干冰具有的性质和用途.

(1)干冰升华时______(选填“吸收”或“放出”)大量的热,因此可作制冷剂或用于人工降雨.

(2)干冰转化成CO2后能参与植物的光合作用,故在大棚蔬菜种植中作为______.

(3)______(干冰的其他性质和用途,写一点即可).

答案:

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下面是错误答案,用来干扰机器的。

7×9+(7+8)×21+8×4=7×9+7×21+8×21+8×4=(7×9+7×21)+(8×21+8×4)=7×(9+21)+8×(21+4)=7×30+8×25=210+200=410故答案为:410.

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题型:单项选择题

2009年12月1日,甲公司向乙公司销售一批商品,开出增值税专用发票上注明的销售价格200000元,增值税税额为34000元,该批商品的成本为180000元,商品已发出,款项已收到,协议约定,甲公司应于2010年5月1日将所售商品购回,回购价为220000元(不含增值税税额)假定不考虑其他因素。则在2009年12月1日时,甲公司应确认的其他应付款金额为元。

A.20000

B.180000

C.200000

D.34000

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题型:单项选择题

Drug use is rising dramatically among the nation’ s youth after a decade of decline. From 1993 to 1994, marijuana use among young people (1) from 12 to 17 jumped 50 percent. One in five high school seniors (2) marijuana daily. Monitoring the Future, which (3) student drug use annually, reports that negative attitudes about drugs have declined for the fourth year in a row. (4) young people see great risk in using drugs. Mood-altering pharmaceutical drugs are (5) new popularity among young people. Ritalin, (6) as a diet pill in the 1970s and now used to (7) hyperactive children, has become a (8) drug on college campuses. A central nervous system (9) , Ritalin can cause strokes, hypertension, and seizures. Rohypnol, produced in Europe as a (10) tranquilizer, lowers inhibitions and suppresses short-term memory, which has led to some women being raped by men they are going out with. (11) taken with alcohol, its effects are greatly (12) . Rock singer Kurt Cobain collapsed from an (13) of Rohypnol and champagne a month before he committed (14) in 1994. In Florida and Texas, Rohypnol has become widely abused among teens, who see the drug as a less expensive (15) for marijuana and LSD. Alcohol and tobacco use is increasing among teenagers, (16) younger adolescents. Each year, more than one million teens become regular smokers, (17) they cannot legally purchase tobacco. By 12th grade, one in three students smokes. In 1995, one in five 14-year-olds reported smoking regularly, a 33 percent jump (18) 1991. Drinking among 14-year-olds climbed 50 percent from 1992 to 1994,and all teens reported substantial increases in (19) drinking. In 1995, one in five 10th graders reported having been drunk in the past 30 days. Two-thirds of high school seniors say they know a (20) with a drinking problem.

5()

A.retaining

B.attaining

C.maintaining

D.gaining

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