题干

  2013年5月26日,中国羽毛球队蝉联苏迪曼杯团体赛冠军,成就了首个五连冠霸业.比赛中羽毛球的某次运动路线可以看作是一条抛物线(如图),若不考虑外力因素,羽毛球行进高度y(米)与水平距离x(米)之间满足关系y=-
2
9
x2
8
9
x+ 10
9
,则羽毛球飞出的水平距离为____米.
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同类题1

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    A man walked into a small Irish pub and ordered three beers. Bartender was surprised, but he served that man three beers. One hour later the man ordered three beers again. The very next day that man ordered three beers again and drank quietly at a table. This repeated several times and shortly after the people of the town were whispering about the man, who was ordering three beers at once.

    A couple of weeks later, the bartender decided to clear this out and inquired: “I do not want to pry, but could you explain, why do you order three beers all the time?” The man replied: “It seems strange, isn't it? You see, my two brothers live abroad at the moment, one – in France and another – in Italy. We have made an agreement, that every time we go to pub each of us will order extra two beers and it will help keeping up the family bond”.

    Soon all the town have heard about the man's answer and liked it a lot. The man became a local celebrity. Residents of the town were telling this story to newcomers or tourists and even invited them to that pub to look at Three Beer Man.

    However, one day the man came to pub and ordered only two beers, not three as usual. The bartender served him with bad feeling. All that evening the man ordered and drank only two beers. The very next day all the town was talking about this news, some people pray for the soul of one of the brothers, others quietly grieve.

    When the man came to pub the next time and ordered two beers again, the bartender asked him: “I would like to offer condolences to you, due to the death of your dear brother”. The man considered this for a moment and then replied: “Oh, you are probably surprised that I order only two beers now? Well, my two brothers are alive and well. It's just because of my decision. I promised myself to give up drinking.”

同类题4

阅读下面的文章,完成下列小题。

世界还很年轻

刘丽丽

    ①初中毕业,我考到县城读书,母亲做了个相当前卫的决定:垦荒种棉花,来年用自家的棉絮给女儿做一床新铺盖。在这个精彩纷呈的世界上,彰显母爱的事每天都会发生,没有什么稀奇,唯一不同的就是我感觉她的这个决定又笨又没有必要。

    ②那时环绕在村子四周的都是水田,没有现成的棉花地,就算种出了棉花,变成新被褥至少需要一年的时间。再者,种棉花几乎要天天喷药,否则虫子猖獗,到秋后留不下几个棉桃。但是在成堆的困难面前,母亲大手一挥,她很坚决,她的理由也很简单:女儿考到县城就必须配好的被褥,公家发的她信不过。

    ③开学后我就忙碌自己的学业,母亲也忙,忙秋收,忙着打听种棉花的事。那时候村里没有电话,她又不会骑自行车,种棉花的亲戚离我们村十几里地,她都是一步步走着去的,从没有喊过累。她选中的棉田依傍着沟渠,是一块撂荒地,长满了白茅和芦苇。土地解冻之后,母亲就扛着铁锹去垦荒。茅草根和小芦苇的根,把那块地包裹得又密又厚,像一条错综的毯子。这样的地块,掘起来很费劲。往常一锹下去就能翻上来的土,这里得多费几倍的力气。一个春天下来,母亲的脸变得又黑又瘦,以致我回家看到她的模样,吓了一跳。母亲黑了瘦了,但是那块荒地却变得有边有角,平头正脸。种子已经播到地里,盖了白生生的薄膜芜杂的世界在春天中呈现出新的秩序。

    ④学校的功课紧张,她每天如何辛劳我是不知道的。后来听邻居说起,每天下地回来,她就钻进厨房先忙活出一家人的饭食,然后趁着薄暮时分的天光,再钻进棉花趟子里,掐杈子,打花心,捉虫子。干这些活都是零打碎敲的工夫,牺牲的却是她的休息时间。有一回可能是太累了,母亲竟然歪在棉花地旁边的草沟里睡着了。

    ⑤那段时间我的成绩并不稳定,心情晴朗的时候少,阴天的时候多。功课紧张,偏偏班主任又指定让我参加学校的演讲赛。虽说我普通话比较标准,但是以我内向的性格,让我在人前侃侃而谈,甚至连比划带拍桌子的演讲,把观众感动到掉眼泪,我实在觉得为难。当我站在棉花地头跟母亲大吐苦水的时候,就是怀着这样一种抗拒的心情,我想打退堂鼓。

    ⑥那是秋天的清晨,草籽在秋风中陆续成熟,草叶上闪烁着晶莹的光亮。母亲正在棉田里忙碌着,她的腰间系了一块塑料布,防止露打湿衣服,但是裤脚上却已经变得湿漉漉的。她一边掐去疯长的权子,一边仔细翻检棉花嫩蕾上的虫子。在一棵棵棉苗前,母亲的急性子和坏脾气都消失了,她变成了一个极其耐心的人,就像面对着十分宠爱的孩子。是啊,从春天到秋天,田里的无数棵棉花,就是这样一遍遍翻检过去,又抚摸过来的,每一棵棉花上都留下了她的指纹和温度。母亲的情意没有白费,棉花们都很争气,叶子深绿,极力展开的枝权间已经见到累累的棉桃。听完我的诉苦,母亲说:“老师让咱讲是看得起咱,那你就好好地讲。”回头揪下一个被雨水捂烂的桃子,惋惜叹了一口气,继续说,“一遍讲不好,你就多讲几遍。好东西都是熬出来的。

    ⑦最后的这句话突然击中。了我的心。看着黑瘦的母亲,我突然一阵心酸,同时一股莫名的力量在心底泛起。为了我的新铺盖,母亲在“熬”;为了演讲赛的好成绩,我也要“熬”。她虽然讲不出深刻的道理给我听,但她倔强地认定,自己的心血和汗水最终会变成洁白的棉絮,去温暖女儿,让她在白天繁重的课业之后,夜有一个轻盈幸福的梦。为了这份信念,她不喊苦不叫屈,硬生生将一块荒地变成了棉田。那时候,她既要照顾半身不遂的祖父,又要处理一大摊子家务。在焦头烂额里,信念如同一盏孤灯,在黑暗中亮起。循着这光亮,她看到了丰收在望的棉花,她的女儿也读出了一番人生的隽语。

    ⑧多年之后回望,我还记得整日里那个劳碌的身影,记得她的不服输和坚持。这些年来,每当我疲倦偷懒,我便习惯性地向着故乡的方向张望一会儿,然后俯下身子继续我的工作。

    ⑨世界在窗外,未来在远方,亲爱的同学,你准备好出发了吗?希望你的心头也有一盏灯照拂,希望你坚定而努力。正如茨维塔耶娃在诗中写的那样:

    ⑩世界还很年轻,一切都将发生,为了你能到来。

(选自《中学生阅读》2018年第7期)