题干

食盐是重要的调味品,精盐是由粗盐提纯而来,在提纯过程中通常不需要的操作是

A:蒸发

B:吸附

C:过滤

D:溶解

上一题 下一题 0.0难度 选择题 更新时间:2018-03-19 08:11:54

答案(点此获取答案解析)

B

同类题3

阅读理解

Bicycle Safety

    Operation  Always ride your bike in a safe, controlled manner on campus. Obey rules and regulations. Watch out for walkers and other bicyclists, and always use your lights in dark conditions.

    Theft Prevention Always securely lock your bicycle to a bicycle rack---even if you are only away for a minute. Register your bike with the University Department of Public Safety. It's fast, easy, and free. Registration permanently records your serial number, which is useful in the possible recovery of the bike stolen.

Equipment.

    Brakes  Make sure that they are in good working order and adjusted properly.

    Helmet A necessity, make sure your helmet meets current safety standards and fit properly.

    Lights Always have a front headlight---visible at least 500 feet in front of the bike. A taillight is a good idea.

Rules of the Road

    Riding on Campus  As a bicycle rider, you have a responsibility to ride only on streets and posted bicycle paths. Riding on sidewalks or other walkways can lead to a fine. The speed limit for bicycles on campus is 15mph, unless otherwise posted. Always give the right of ways to walkers. If you are involved in an accident, you are required to offer appropriate aid, call the Department of Public Safety and remain at the scene until the officer lets you go.

Bicycle Parking Only park in areas reserved for bikes. Trees, handrails, hallways, and sign posts are not for bicycle parking, and parking in such posts can result in a fine.

If Things Go Wrong

    If you break the rules, you will be fined. Besides violating rules while riding bicycles on campus, you could be fined for:

No bicycle registration---------------------------------$25

Bicycle parking banned------------------------------$30

Blocking path with bicycle ---------------------------$40

Violation of bicycle equipment requirement -----------$35

同类题4

阅读下文,回答问题。

萝卜花丁立梅

      ①萝卜花是一个女人雕的,用料是萝卜,她把它雕成一朵朵月季花的模样。花盛开,很喜人。

      ②女人在小城的一条小巷子里摆地摊儿,卖小炒。一小罐煤气,一张简单的操作平台,木板做的,用来放锅碗盘碟,她的摊子就摆开了。她卖的小炒只三样:土豆丝炒牛肉,土豆丝炒鸡蛋,土豆丝炒猪肉。

      ③女人30岁左右,瘦,皮肤白皙,长头发用发卡别在脑后。惹眼的是她的衣着,整天沾着油锅的,应该很油腻才是,却不。她的衣服极干净,外面罩着白围裙。衣领那儿,露出里面的一点红,是红毛衣,或红围巾。她过一会儿,就换一下围裙,换一下袖套,以保持整体衣着的干净。很让人惊奇且喜欢的是,她每卖一份小炒,就在装给你的方便盒里放上一朵雕刻的萝卜花。这样装在盒子里的,才好看。她说。

      ④不知是因为女人的干净,还是她的萝卜花,一到吃饭时间,女人的摊子前,总围满人。五块钱一份的小炒,大家多很耐心的等待着。女人不停地翻铲,而后装在方便盒里,而后放上一朵萝卜花。整个过程,充满美感。于是,一朵一朵素雅的萝卜花,就开到了人的饭桌上。

      ⑤我也去买女人的小炒。去的次数多了,渐渐知道她的故事。

      ⑥女人原先有个很殷实的家。男人是搞建筑的,很有些钱。但不幸的是,在一次建筑中,男人从尚未完工的高楼上摔下来,被送进医院,医院当场就下了病危通知书。女人几乎倾尽所有,抢救男人,才捡回半条命——男人瘫痪了。

      ⑦生活的优裕不再。年幼的孩子,瘫痪的男人,女人得一肩扛一个。她考虑了许久,决心摆摊儿卖小炒。有人劝她,街上那么多家饭店,你卖小炒能卖得出去吗?女人想,也是。总的弄点和别人不一样的东西吧?于是她想到了雕刻萝卜花。当她静静地坐在桌旁雕画时,她突然被自己手上的美镇住了,一根再普通不过的胡萝卜,在眨眼之间,竟能开出一小朵一小朵的花来。女人的心,一下子充满期望和向往。

      ⑧就这样,女人的小炒摊子,摆开了,并且很快成为小城的一道风景。下班了赶不上做菜的人,都会相互招呼一声,去买一份萝卜花吧。就都晃到女人的摊儿前来了。

      ⑨一次,我开玩笑地问女人,攒了多少钱了?女人笑而不答。一小朵一小朵的萝卜花,很认真地开在她的手边。

      ⑩不多久,女人竟出人意料地盘下了一家酒店,用她积攒的钱。她负责配菜,她把瘫痪的男人,接到店里管账。女人依然衣着干净,在所有的菜肴里,依然喜欢放上一朵她雕刻的萝卜花。菜不但是吃的,也是用来看的呢。她说,眼睛亮着。一旁的男人,气色也好,没有颓废的样子。

      ⑪女人的酒店,慢慢地出了名。提起萝卜花,大家都知道。

      ⑫生活,也许避免不了苦难,却从不会拒绝一朵萝卜花的盛开。

                                                                                                                                                     (选自《语文月刊》2008年,有改动)