抗体是一种特殊的（    ）

阅读下面文段，回答后面问题。
         小草偷偷地从土里钻出来，嫩嫩的，绿绿的。园子里，田野里，瞧去一大片一大片满是的。坐着，躺着，打两个滚，踢几脚球，赛几趟跑，捉几回迷藏。风轻悄悄的，草软绵绵的。
         桃树、杏树、梨树，你不让我，我不让你，都开满了花赶趟儿。红的像火，粉的像霞，白的像雪。花里带着甜味儿；闭了眼，村上仿佛已经满是桃儿、杏儿、梨儿。花下成千成百的蜜蜂嗡嗡地闹着，大小的蝴蝶飞来飞去。野花遍地是：杂样儿，有名字的，没名字的，散在草丛里像眼睛，像星星，还眨呀眨的。

李老师要对初三（1）、（2）班的考试情况进行分析，在两个班里随机抽取了30名学生的考试成绩：87、75、94、60、51、86、73、89、93、67、57、88、82、66、88、88、85、67、91、65、78、89、80、72、78、84、90、64、71、86．

根据上述消息回答下列问题：

（2）估计这两个班级本次考试成绩在80分及80分以上的占____ %；

（4）是否一定能根据这30名学生的成绩估计全区考试成绩？答：____ ．

（5）80～90组的平均分为____ ，中位数为____ ．

阅读理解

    What did you do on April 23, World Book Day, last year? Did you find some interesting books to read? Now let me introduce some good books for you to read.

Title: Dear Andreas
Author: Long Yingtai＆Andreas

Andreas is a college student studying in Germany. His mother is a writer working in Taiwan. By writing letters to each other for more than three years, Long Yingtai says she clearly understands what an 18-year-old man is like, Andreas says he knows his mother better. This is a great book full of love. Don't miss it.
Title: Climate Change+2 Degrees
Author: Yamamoto Ryoichi

If the earth's temperature went up 2℃, what would happen? In this book we learn about the history, today's situation and the future of global warming. The author also tells us proper and useful ways to protect our world.
Title: The Methods and Madness Inside Room 56
Author: Rafe Esquith

Perhaps the most famous fifth-grade teacher in America, Rafe Esquith, helps his children understand literature, love life, and become happy, self-confident people using his successful methods in his Los Angeles public school classroom. He has created surprising miracles. This is a powerful book. You'd better read it.
Title: The Last Lecture
Author: Randy Pausch

Randy Pausch, a professor from New York was asked to give a lecture. He knew it would probably be his last lecture, because he was dying of illness. His lecture wasn't about dying, but about getting over the difficulties, helping others to realize their dreams.

It's      now．