题干

实验室制取氧气的过程中,可以利用如图装置进行收集、干燥等操作.下列对应的处理方式正确的是 (  )


A:方式①:瓶内装浓硫酸干燥氧气,氧气由a进入

B:方式②:瓶内装满水后用排水法集气,由a进气收集氧气

C:方式③:向上排空气集气,由a进气收集氧气

D:方式④:排出瓶中原有的氧气,由a通入水逐步排出氧气

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答案(点此获取答案解析)

B

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    Thirteen-year-old American Jessica Goldstone wants to be a fashion designer when she finishes school. She thinks her designs would be more exciting than clothes bought from stores. But until this month, Jessica has never touched a sewing machine(缝纫机).

    After her first class, Jessica and six other girls aged 9 to 13 said that sewing was fun, cool and challenging.

    These students at Fabrics' Sew Fun class show that the sewing machine is becoming popular again.

    “There have been a lot of teens getting excited about sewing,” said a sewing company worker Donna Smith. “Some of them come from the Project Runway TV show,” she said. This TV show is an exciting weekly contest to make a great fashion designer. Every week one contestant (参赛者) fails the test and has to leave the contest.

    The number of people who joined sewing class summer camps grew by 10 percent this year. That's good news for companies that make sewing machines and publish sewing magazines. The Singer Sewing Company sold nearly 3 million sewing machines in the United States last year. This is about twice as many as in 1999.

    Sewing machines have been around for more than 150 years, but they have changed a lot since your grandmother was a girl.

    Spencer Carmel started sewing lessons after getting a sewing machine for her 11th birthday. She has sewn a lot by hand, but she wants to make more difficult things. Spencer's class recently made hats.

    Another member of the class, Kelsey Oen, 9 years old, needed time to get used to her machine, but soon she could use it well. By the end of the class, Kelsey was happy and wearing her new hat.

同类题4

(二)

凶猛的暴风雪像狂人似的袭击着薄薄的帐篷,死神正在悄悄地走来,就在这样的时刻,斯科特海军上校回想起了与自己有关的一切。因为只有在这种从未被人声冲破过的极度寂静之中、他才会悲壮地意识到自己对祖国、对全人类的亲密情谊。但是在这白雪皑皑的荒漠上,只有心中的海市蜃楼,它召来那些由于爱情、忠诚和友谊曾经同他有过联系的各种人的形象,他给所有这些人留下了话。斯科特海军上校在他行将死去的时刻,用冻僵的手指给他所爱的一切人写了书信。

②斯科特海军上校的日记一直记到他生命的最后一息,记到他的手指完全冻住,笔从僵硬的手中滑下来为止。他希望以后会有人在他的尸体旁发现这些能证明他和英国民族勇气的日记,正是这种希望使他能用超人的毅力把日记写到最后一刻。最后一篇日记是他用已经冻伤的手指哆哆嗦嗦写下的愿望:"请把这本日记送到我的妻子手中!"但他随后又悲伤地、坚决地划去了"我的妻子"这几个字,在它们上面补写了可怕的"我的遗孀"。

③住在基地木板屋里的伙伴们等待了好几个星期,起初充满信心,接着有点忧虑,最后终于愈来愈不安。他们曾两次派出营救队去接应,但是恶劣的天气又把他们挡了回来。一直到南极的春天到来之际,10月29日,一支探险队才出发,至少要去找到那几位英雄的尸体。11月12日,他们到达那个帐篷,发现英雄们的尸体已冻僵在睡袋里,死去的斯科特还像亲兄弟似的搂着威尔逊。他们找到了那些书信和文件,并且为那几个悲惨死去的英雄们垒了一个石墓。在堆满白雪的墓顶上竖着一个简陋的黑色十字架。

④在英国国家主教堂里,国王跪下来悼念这几位英雄。

⑤一个人虽然在同不可战胜的厄运的搏斗中毁灭了自己,但他的心灵却因此变得无比高尚。所有这些在一切时代都是最伟大的悲剧。