题干

过抛物线y2=2px(p>0)的焦点F的直线l与抛物线交于点B,C两点,l与抛物线的准线交于点A,且|AF|=6, AF =2 FB ,则|BC|=(   )

A:92

B:6

C:132

D:8

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答案(点此获取答案解析)

A

同类题4

阅读下面短文,掌握大意,然后从1-20各题所给的四个选项(A、B、C和D)中,选出最佳答案。

        My husband, Bob, died in January 2004. His death was unexpected as well. I 1 condolences(哀悼)from people I hadn't heard from in years: letters, cards, flowers, calls, and visits. I took a bad knock with 2. I was so struggling to3the whys and hows of this terrible thing that had happened to my family, knowing in my heart that there really were no 4. It's just all so sad.

        One message5me deeply. I received a letter from my best friend from sixth6 through high school. We had drifted somewhat since 7 in 1959, as she stayed in our home town and I did not. 8 it was the kind of friendship that could quickly resume even if we9touch for five or ten years.

        Her husband, Peter, had died perhaps 20 years ago at a young age, 10her with deep sorrow and heavy 11: finding a job and raising three young children. She and Pete, 12 Bob and I, had shared one of those rare, close, "love-of-your-life-you-can-never-forget" 13.

        In her letter she 14 an anecdote about my mother who had passed away years ago. She wrote, "When Pete died, your dear mother 15me and said, 'Trudy, I don't know what to say...so I'll just say I love you.'"

        She closed her letter to me repeating my mother's words of so long16, "Bonnie, I don't know what to say...so I'll just say I love you."

        I felt I 17 almost hear my mother speaking to me now. What a 18 message of sympathy! How dear of my friend to cherish it all those years and then 19 it on to me.I love you. 20 words. A gift. A legacy(遗赠物).

同类题5

阅读下面的文言文,完成下列各题。

    王鼎,字定九,陕西蒲城人。少贫,力学,尚气节。赴礼部试至京,大学士王杰与同族,欲致之,不就。杰曰:“观子品概,他日名位必继吾后。”嘉庆元年,成进士,选庶吉士。丁母忧,服除,授编修。两以大考升擢,累迁内阁学士。十九年,授工部侍郎。仁宗谕曰:“朕不知汝,亦无人保荐。因阅大考考差文字,知汝学问。屡次召见奏对,知汝品行。汝是朕特达之知。”调吏部,兼署户部、刑部。二十三年,兼管顺天府尹事,复谕曰:“朕初意授汝督抚,今管顺天府尹,犹外任也。且留汝在京,以备差往各省查办事件。”自是数奉使出按事鞫狱。二十四年,调刑部,又调户部。浙江德清徐倪氏因奸谋毙徐蔡氏狱三年不决,按察使王维询因自尽,巡抚程含章与按察使祁埙鞫之,甫得情而犯妇在监自缢。宣宗特命鼎典乡试,就治其狱,廉得徐故富家,以狱破其产,官吏多受赇,勾结朦庇,致狱情诪幻。悉发其覆,置之法,浙人称颂焉。道光六年,授户部尚书。八年,回疆平,以赞画功,加太子太保,绘像紫光阁。二十一年夏,河决祥符,命偕侍郎慧成往治之,寻河督。议者以水势方涨,不宜遽塞,请迁省城以避其冲,鼎持不可,疏言:“河灌归德、陈州及安徽亳、颍,合淮东注洪泽湖,湖底日受淤。万一宣泄不及,高堰危,淮、扬成巨浸,民其鱼矣!无论舍旧址、筑新堤数千里,工费不赀,且自古无任黄水横流之理。请饬户部速具帑,期以冬春之交集事。不效,愿执其咎。”具陈民情安土重迁、省垣可守状。初至汴城,四面皆水,旦夕且圮,躬率吏卒巡护,获无恙。工兴,亲驻工次,倦则寝肩舆中。次年二月,工竣。叙功,晋太子太师。积劳成疾,命缓程回京。自禁烟事起,英吉利兵犯沿海,鼎力主战。至和议将成,林则徐以罪谴,鼎愤甚,还朝争之力,宣宗慰劳之,命休沐养疴。越数日,自草遗疏,劾大学士穆彰阿误国,闭户自缢,冀以尸谏。军机章京陈孚恩,穆彰阿党也。灭其疏,别具以闻。上疑其卒暴,命取原稿不得,于是优诏悯惜,赠太保,谥文恪,祀贤良祠。后陕西巡抚请祀乡贤,特诏允之。鼎清操绝俗,生平不受请托,亦不请托于人。卒之日,家无余

(节选自《清史稿•列传第一百五十》)

【注】①大考:清代翰林、詹事的升级考试。②考差:科举制度中考官的考选差派制度。