Rt△ABC中，∠ACB=90°，若∠ACD=50°，则与∠BCD相邻的外角度数是（　　）

阅读短文并选择方框内的适当形式填空，每空仅填一个词，每个词仅用一次。

as, close, end, family, large, last, over, performance, say, tradition

    CCTV New Year's Gala(春晚) is a Chinese New Year special produced by China Central Television. The program begins at 8:00 PM and ____  until about 1:00 AM on the first day of the New Year.
    The program has received extremely ____  audiences(观众), which have grown greatly  ____ the years. As the Chinese New Year’s Eve is a time when the____ members get together, the Gala adds a pleasant mood to the house ____  people sis in front of their TV set laughing, discussing and enjoying the ____ . It has become a ____ in China to watch the New Year’s Gala. Around 1:00 in the early morning, the program ____ with the song Can't Forget Tonight.
    To bring audiences even ____  to the yearly show, the Gala organizers have tired many ways to make the program more attractive. It is ____  that there will be no advertisements this year so that audiences can be satisfied with a natural and smooth Gala.

Mike's mother was an art teacher then.

等比数列{a_n}共有奇数项，所有奇数项和S_奇=255，所有偶数项和S_偶=﹣126，末项是192，则首项a₁=（   ）

填入下列语段横线处的句子正确的一组是（　　）。（3分）
敏捷的才思、广博的知识和流畅的表达是辩论的前提，而准备是否充分则是辩论胜败的关键。辩论首先要        ；其次要       ；最后，要       。此外，         。要写出简明的辩论提纲。
①在语言表达方面，力求准确、简洁、生动、连贯
②认真研究辩题，从正反两个方面正确把握辩题的内涵，做到“知己知彼” 
③深入分析对方观点，推测对方所持的理由和根据，制定辩论的策略
④广泛搜集与辩题有关的材料，找好论据