题干

为了探究光反射时的规律,某同学将一个平面镜放在水平桌面上,再把纸板ENF放置在平面镜上,如图甲所示 .


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同类题3

阅读下面的文字,完成后面小题。

牛黄

孙万友

    牛黄,中药名,黄牛或水牛的胆囊结石。性凉,味甘苦。功能清热、解毒、定惊。牛黄分多种,有葡萄黄、米碜黄、鸡心黄。最宝贵的为“人头黄”,黄大如人头,价值昂贵。疯癫如狂的患者沏上一杯牛黄茶灌了,当即就可清醒。“人头黄”为稀世珍宝,一般人极少见到。

    陈州解三,就曾得到一颗“人头黄”。

    解三以宰牛为生,也靠牛黄发财。平常买牛,多买瘦牛。牛胆结石,是永远吃不肥的。有一日,解三购得一头老牛,剥开一看,脏内如黄花盛开,解三第一次目睹“人头黄”,简直有点儿不敢相信自己的眼睛,不禁失声叫道:“人头黄!”

    不料隔墙有耳,被邻家夏二听了去。夏家与解家只一墙之隔,墙上爬满丝瓜秧。夏二搬梯爬墙,把脸匿在丝瓜秧里,一下子看了个清楚。

    夏二是个皮货商,往常解三晾晒的牛皮牛鞭,多由他购去再到南阳倒卖。夏二自然知道“人头黄”的价值,回到屋里,怔怔然许久,决定要盗得解三的人头黄。

    半夜时分,夏二登梯爬上墙头,用系牢的绳索溜到解家院里。他先静耳听了听动静,然后用尖刀拨门。不料门没栓,他深感不妙,心想可能解三有防,便急忙藏了尖刀,匆匆顺原路而回,躺在床上,心中还在“扑腾”。他很是懊悔自己见财眼开干了愚事,为此翻来覆去折腾了一夜,直到黎明前才迷糊过去。不料刚想沉睡,突然听得解三来借梯子。

    夏二一听借梯子,大惊失色,心想这解三大概是故意来试探虚实!更可悔的是昨夜只顾害怕,竟忘记把梯子从墙边挪开!为不让解三看出破绽,他急忙披衣穿鞋,想把解三稳在屋里,然后悄悄把梯子挪开,以除解三的疑心。不料他还未下床,却被解三拦住了,说:“二哥你睡你睡!进门时我就看到了梯子,在墙上搭着呢!”

    夏二一听此言,如傻了一般,直等解三走了,他还未醒过神来。这一天,夏二如得了重病,心郁如铅,脑际里全是解三的影子。那墙上被绳索勒的痕迹他是否看到了……一连几天,这等问题在夏二脑子里来回翻腾,吃不香睡不宁,双目开始痴呆,偶尔还自言自语,时间一长,夏二失去了理智,开始在满街疯跑。

    夏家人很着急,以为夏二患了什么邪症,又求神又烧香,均不济事,最后请来了一名老郎中。老郎中进门并不急于给夏二看病,而细心观察。几天过后,他才对夏家人说:“你们当家的病是心疾所至,一般药物只能顾表而不能治里,眼下只能用人头黄可以根除!只是这人头黄为稀世珍物,一般药店是买不到的!”

    不想在一旁自言自语的夏二一听到“人头黄”三字,突然瞪大了眼睛,下意识地接道:“解三家有人头黄!解三家有人头黄……”

    夏二的妻子为治夫疾,就以试探的心理去解家求要人头黄。谁知解三一听脸色惧白,连连地说:“我没有人头黄!我没有人头黄……”

    夏妻失望而归,对老郎中说:“解三说他没有人头黄!”夏二一听怔然如痴,许久了,突然倒头睡去。夏二一睡三天三夜,像达到了某种心理平衡,竟奇迹般地好了。

    可是,没过几日,解三竟也疯了,而且比夏二疯得还厉害,到处嚎叫:“我没有人头黄!我没有人头黄……”

    解家人急忙请来那老郎中给解三瞧病,老郎中望着解三,让人请来夏二,暗地安排了一番,然后让夏二对解三说:“你没有人头黄!”

    不料解三一听此言,更是惊恐,“忽”地挣脱了老郎中的手,边跑边喊:“我不是不给夏二治病,我压根儿就没人头黄呀!”

    老郎中望着疯跑的解三,痛苦地摇摇头,对解家人说:“解师傅的病没救了,没救了!”

    夏二觉得很惋惜,想想自己的所为,很是有点儿后怕!

    几年以后,解三被冻死野外。解三死后,其子承父业,数年后翻盖新房,扒旧屋的时候,扒出了那个人头黄。解三之子只认得一般牛黄,却不认得人头黄为何物,便求夏二指教。夏二望着那人头黄,面色冰冷,许久了才说:“是一块普通的药草,你留它没用,放我这儿吧!”

    解三之子把人头黄送给了夏二。夏二后来用人头黄救了许多人,分文不取,有求必应。这样过了三十余年,夏二已年近八旬。临终的时候,他唤过家人,从怀里取出那颗人头黄,安排说:“这块药物,只可施舍,不可贪利!”

    不料夏二死后,其子夏仲不守诺言,将人头黄卖了,成了方圆几十里的富户。家中子女都因家中富有而不行正道,夏仲最后也因此悬梁自尽。

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同类题5

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    Filmmaker Jennifer Nelson had to pay $1,500 to have “Happy Birthday to You” sung in the movie she's making. The money went to Warner Music Group, a company that claims to own the copyright on the song. A copyright is the legal right to use or sell a creative product such as a song, a TV show, a book, or a work of art. Warner has claimed the copyright for “Happy Birthday to You” since 1988.

    “I never thought the song was owned by anyone,” Nelson said in an e-mail to The New York Times. “I thought it belonged to everyone.”

    Nelson's movie is a documentary — a film that uses pictures and/or interviews with people to create a factual report of real-life events — and is actually about the history of the “Happy Birthday” song itself.

    Two sisters named Mildred and Patty Hill wrote a song called “Good Morning to All” in 1893. Over a short period of time, people began to sing the words “happy birthday to you” in place of the original lyrics to the tune of the Hill sisters' song.

    A number of history experts say that there is no record of who actually wrote the “Happy Birthday to You” lyrics. Historians also say there is no way to know when the general public began singing the “Happy Birthday” song, but they believe it was being sung by the public long before it was printed and owned by a company.

    Nelson's lawyers say this piece of music's history proves that “Happy Birthday to You” belongs to everyone in the general public. That would mean Warner Music Group has no right to charge anyone a fee to sing the song in any setting.

    Experts estimate that Warner/ Chappell, the publishing division of the Warner Music Group, has made about $2 million a year from licensing fees for “Happy Birthday to You.”

    Nelson's lawyers are asking a court in New York City to order Warner/Chappell to return fees they have collected over the past four years for use of the “Happy Birthday” song.