若O是四边形ABCD对角线的交点且OA=OB=OC=OD，则四边形ABCD是（   ）

如图所示测量大气压强的装置，玻璃管长约1m，槽内装有水银．下列说法正确的是（　　）

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分解因式：a³﹣25a=．

利用酵母菌发酵酿制酒的过程中，温度过高或过低都会影响酵母菌发酵．下图能正确反应酵母菌发酵时产酒量随温度变化的曲线的是（   ）

下列有关自行车的使用说法正确的是（  ）

What's wrong with Linda?

如图所示，同学们在做“测量物质的密度”实验，实验步骤如下：

①把天平放在水平桌面上，游码移到标尺左端零刻线处，观察到指针如图甲所示，他应将平衡螺母向调节，使天平平衡。②把小酒杯放在天平左盘，天平平衡时，右盘中的砝码和游码在标尺上的位置如图乙所示，则小酒杯的质量为g。③在量筒中倒入50ml的水，放入小酒杯后水面所对应的刻度如图丙所示，则小酒杯的密度为kg/m³。

科学研究常常采用转换、模拟等研究方法，下列四个课本中的实验与其他三个所采用的研究方法不同的是(    )

如图，已知△ABC，

将一个有45°角的三角板的直角顶点放在一张宽为3cm的纸带边沿上，另一个顶

点在纸带的另一边沿上，测得三角板的一边与纸带的一边所在的直线成30°角，如图（3），

则三角板的最大边的长为（   ）

一辆在平直的公路上行驶的汽车车厢顶部挂着一个小球，当突然出现如图所示的情景时，汽车在做（选填“加速”“匀速”或“减速”）运动；若汽车向左做匀速直线运动，则小球受到绳子的拉力与小球受到的重力（选填“是”“不是”或“可能是”）一对平衡力。

图所示的四种现象中，其物态变化属于放热过程的是（   ）

阅读理解

    On my recent trip to Sydney with my parents, we visited a wildlife park.

    The wildlife park has lots of different animals. Some are native（当地的）to Australia and can only be found there. There are over 600 animals there, including kangaroos, koalas and crocodiles（鳄鱼）. They are living in their natural environment. I like the wildlife park better than a zoo where most of the animals are in cages（笼子）.

    We first spent some time with the kangaroos. We could touch and feed them. It was very exciting to be so close to them. There were koalas there too. They looked very cuddly（令人想拥抱的）. Although we couldn't touch them, I got to take a photo with one. It is a wonderful souvenir（纪念品）of my holiday in Sydney.

    The wildlife park has plenty of freshwater and saltwater crocodiles. Some of them are really big and scary（吓人的）with huge teeth! I did not want to get too close to them.

    There was also a bird show. The keepers showed us different species（种类）they had. I saw an old parrot which could "talk". It made a great impression on me.

    I enjoyed the trip very much. There was so much to see.

下列二次根式的运算正确的是（  ）

如图所示，△ABC和△ECD均为等边三角形，B、C、D三点共线，AD与BE交于点O．求∠BOD的度数．

20世纪70年代末，中国进入了改革开放和现代化建设的新时期。三十多年的征程，铸就了一个民族近百年的梦想。三十多年来，中国发生了翻天覆地的变化。阅读下列图文材料，回答相关问题:

材料一　

材料二　轻重工业在工业总产值中所占比重表

材料三　深圳的变化

1924年黄埔军校成立，在课程设置上，蒋介石提出，除了要学战术学、军制学、兵器学，中国国民党史、帝国主义侵略史、世界革命史等相关的政治性科目也必不可少。材料反映了黄埔军校（   ）

如图所示，已知∠1=22°，∠2=28°，∠A=56°，则∠BOC的度数是.

在探究蹄形磁体周围磁场的实验中，老师将玻璃板平放在磁体上，并均匀地撒上一层铁屑，轻敲玻璃板，铁屑就会有序地排列起来，如图。对实验中有关现象的分析不正确的是(   )

阅读下列短文，从下面每小题的A、B、C、D四个选项中选出最佳选项。

    A nice day out for the whole family! Come and see beautiful animals in our zoo! Scientists will give wonderful lessons about animals every Tuesday! Don't miss it!

Area A	Koalas live in the trees and like eating grass and leaves. Their lifespan is about 14 years. You can learn about their habits and why they sleep for nearly 20 hours a day. showtime: 1: 30 p.m.-3: 30p.m. except Friday Kangaroos can jump at a speed of 13-15 miles per hour. They can live for at most 22 years. showtime: 3: 30 p.m.-5: 30p.m. except Friday
Area B	Crocodiles have the strongest bite of all animals in the world. Their lifespan is 45-100 years. The crocodiles here are 76 years old! Showtime: 10: 00a.m.-11: a.m. except weekends Tortoises can live for more than 100 years! They can grow to about 1 metre tall. Showtime: 9: 00a.m. except weekends
Area C	Tigers are the largest of the Big Cats weighing up to 300 kg! Watch our tigers swimming in the water. Showtime: 11: 00a.m.-11: 30a.m. except Friday Camel's humps actually stores fat, not water! Showtime: 12: 30p.m.-1: 20p.m. except Friday
Area D	Parrots here have four toes on each foot—two facing the front and two facing the back. Showtime: 9: 00 a. m.—5: 30 p. m. except weekends
Ticket Prices	Adult: $55    Child: $45 Family (2 adults+2 children): $172