A，B，C，D为圆上顺次四点，且弧AB，BC，CD，DA的度数之比为2：3：4：

阅读理解。

                                                                        Koala bear 

Appearance: A little short and fat animal, looking like a toy bear.

Place: Australia.

Food: Eucalyptus leaves(桉树叶)-2.5 pounds of leaves per day for an adult koala,and I pound of leaves and

         some mother's milk per day for a baby koala.

Habit: Sleep all day and eat at night.

Interesting things: A baby koala is very small when it is born.It has no hair, and it can't see either. It lives in

                           its mother's pouch (育儿袋) for 5～7months. 

                                                                         kangaroo

Appearance: Short front legs, long and strong back legs. Looking like a big mouse.

Place: Australia. 

Food: Grass.

Interesting things: It is the national symbol (象征) of Australia. There are more kangaroos than people in this

                           country.

1.If someone sees a newly born koala bear, he will be surprised because it's very ______. [ ]

A.weak

B.small

C.short

D.black

2.A baby koala can't live without ______. [ ]

A.its father

B.grass

C.its mother

D.people

3.the kangaroo is the national symbol of ______. [ ]

A.Canada

B.Australia

C.America

D.Britain

4.There are more ______ than people in Australia. [ ]

A.kangaroos

B.koala bears

C.monkeys

D.elephants

5.We can guess that koala bears and kangaroos are ______ animals in Australia. [ ]

A.beautiful

B.playful

C.endangered

D.popular

滑轮直径与钢丝绳直径之比应不小于（）。

A、10

B、12

C、14

D、16

油发的基本原理是什么﹖

下列每个选项中两个数据相等的是( )

A．(66)₈，(55)₁₀
B．(76)₈，(60)₁₀
C．(45)₈，(37)₁₀
D．(53)₈，(55)₁₀

男性，5岁。跌倒时左手掌着地，查体：肘部向后突出并处于半屈状，肘部明显肿胀及压痛，肘后三角关系正常。

最可能的诊断是（）

A.伸直型肱骨髁上骨折

B.屈曲型肱骨髁上骨折

C.肘关节脱位

D.桡骨小头半脱位

E.尺骨鹰嘴骨折