题干

保留水分是蔬菜和水果保鲜的一个方面,为了探究影响蔬菜和水果水分散失快慢的因素,小军同学作出了以下猜想:

猜想①:与蔬菜所处环境的温度有关

猜想②:与蔬菜的表面积有关

猜想③:与蔬菜的表面空气的流动速度有关.

为了检验上述的猜想是否正确,小军按下图进行了四次实验(实验器材除B中有未剖开的胡萝卜,其余的均已剖开)

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同类题4

阅读下面短文, 从短文后各题所给的四个选项(A、B、C、D)中, 选出可以填入空白处的最佳选项。

    I was a single parent of four small children, working at a low-paid job. Money was always tight, but we had a 1 over our heads, food on the table, clothes on our backs, and if not a lot, always 2. Not knowing we were poor, my kids just thought I was 3. I've always been glad about that.

    It was Christmas time, and although there wasn't 4 for a lot of gifts, we planned to celebrate with a family party. But the big 5 for the kids was the fun of Christmas 6.

    They planned weeks ahead of time, asking 7 what they wanted for Christmas. Fortunately, I had saved $120 for 8 to share by all five of us.

    The big9 arrived. I gave each kid a twenty-dollar bill and 10 them to look for gifts of about four dollars each. Then everyone scattered(散开). We had two hours to shop; then we would 11 back at the “Santa's Workshop”.

    Driving home, everyone was in high Christmas spirits(情绪), 12 my younger daughter, Ginger, who was unusually 13. She had only one small, flat(瘪的) bag with a few candies—fifty-cent candies! I was so angry, but I didn't say anything 14 we got home. I called her into my bedroom and closed the door, 15 to be angry again. This is what she told me.

    “I was looking 16 thinking of what to buy, and I 17 to read the little cards in the ‘Giving Trees.' One was for a little girl, four years old, and all she 18 for Christmas was a doll(玩具娃娃). So I took the card off the tree and 19 the doll for her. We have so much and she doesn't have anything.”

    I never felt so 20as I did that day.

同类题5

阅读下面文章,完成小题。

        ①坐在办公桌前,不经意的向窗外望去,眼前的情景顿时令我惊呆了———窗外的枝丫上何时挂满了红花,那花开得轰轰烈烈,红红火火,而我竟浑然不觉。
        ②搬到政府大楼上班已经半年多了,原以为每日与我隔窗相望的是一棵枯老的树:虽然挺拔,却仅有一般粗细的躯干;叶子稀稀拉拉,枝干也不繁茂;终年不见开花、结果,对此,我总觉得有些沮丧。院子里还有许多常青植物,虽然欣欣向荣,却总觉得没有些许的变化,似乎有些呆板。看着灰白色的枝干笔直地冲向云霄,我在认知里仔细搜寻:我曾把它当作是作家茅盾笔下的白杨树———笔直的干,笔直的枝……哪怕只有碗来粗细罢,它却努力向上发展;我也曾把它当作是鲁迅《秋夜》里枣树———默默地铁似的直刺着奇怪而高的天空。它虽光秃秃的一叶不挂,但骨子里却透着精气。然而,冬去春来,这毫不起眼的枯树,竟喷出了“火焰”,硕大的花朵像一团团火苗在枝头跳跃着,燃起了新的生命。这突如其来的绽放,似那腾空而起的火树银花定格在咫尺之间,好美!
       ③这棵毫不起眼的枯树就是木棉树,直到今天我才真正认识了它。春天时,一树橙红;夏天绿叶成荫;秋天枝叶萧瑟;冬天秃枝寒树。早春二、三月,木棉萧瑟的枯枝上先是绽故了满树火红,接着新芽才萌发。木棉树花落后长出长椭圆形的葫果,成熟后果英开裂,果中的棉絮随风飘落。朵朵棉絮飘浮空中,如下六月雪一般,有一番特别的情趣。
         ④木棉树因其属于速生、强阳性树种,树冠总是高出附近周围的树群,以争取阳光雨露,这种奋发向上的精神及鲜明似火的大红花,被人誉之为英雄树、英雄花。有记载最早的“英雄花”见于清人陈恭尹,他在《木棉花歌》中形容木棉花“浓须大面好英雄,壮气高冠何落落”。
        ⑤正当我陷入沉思,“啪”的一声,一朵碗大的木棉花猛然地跌落,掷地有声、干脆利落。拾起木棉花,我突然觉得有些惋惜,那还是开的正盛的花朵,娇艳欲滴的花瓣里饱含着充足的水分,通体透红的花朵仍完好无损。在这一年的大部分时间里,它是安静的,默默无闻地积蓄着力量,而后这一树的灿烂,迸发了参天的无限辉煌。一年的精华沉淀,一年的淡定从容,直到此时此刻 , 满树的红花见证了它的存在,满堂的喝彩彰显了它的内力。
        ⑥我手捧落花,泪流满面———木棉花落在了树下的草坪上,还是很美。花开花落之间,你已向世人展现了最华美的乐章,用心、用情精心谱写。这,就已足够了!古往今来,有多少人,穷其一生,就是为了成就一项人生事业名垂青史;“养兵千日,用在一时”,保家卫国的士兵们在平时,同样是普普通通的匹夫,而在某一场战役中,因着心中爱祖国爱人民的无限赤子情怀,他们将毕生追求化作祖国锦绣河山。其实各行各业的人们也一样,他们都是国家建设的基石,都是人民生活稳定的护卫者,他们同样用自己平凡的人生在平凡的岗位上做出不平凡的业绩,实现自己的人生价值。
         ⑦而你———火红的木棉花,一年一次在天地灰蒙蒙的四月展现自己,你的高冠艳花将一切漠视甚至耻笑你的狂徒温柔的扫荡。何须追求永世的绚烂呢?一步一个脚印,脚踏实地,生活所给予每一个生命的尊重都是一样的,所得所失何苦斤斤计较。不追求个性张扬,却愿如你默默无闻,始终透着那般无视权贵又不谐峰蝶的傲然正气,最后给人一种惊喜,生命也同样精彩。