读下图，完成下列要求 （1）图中①地区荒漠化的自然原因是____________

阅读短文，选择正确选项。

       Rita Libby is from Canada, but she lives in London. She isn't married. She works in a hospital. Rita has a

car and usually drives to work. She leaves home at half past eight and arrives at the hospital at nine o'clock. She

likes her job, but she likes the weekends, too.

       On Saturdays she sometimes goes shopping. She goes to the centre of London by train. On Sundays she

eats in a restaurant with friends. She never cooks on Sundays.

1. What's the woman's first name? [ ]

A. Rita.

B. Libby.

C. Canada.

D. London.

2. Rita usually             to work. [ ]

A. goes

B. walks

C. runs

D. drives

3. Rita arrives at the hospital at            . [ ]

A. 8:00

B. 8:30

C. 9:00

D. 9:30

4. Rita goes shopping by            . [ ]

A. train

B. bus

C. car

D. bike

5. What does Rita do on Sundays? [ ]

A. She eats outside.

B. She doesn't do anything.

C. She cooks at home.

D. She goes to work, too.

下列属于生物应激性现象的是[ ]

A．水稻的茎有气孔

B．碰触含羞草后，叶卷曲

C．竹节虫的形态与竹节相似

D．北极熊有白色的体毛

预防接种的免疫学效果评价指标是（）

A.二代发病率

B.感染率

C.阳转率

D.保护率

E.相对危险度

当加油岛被加油车辆撞坏时，该如何处理？（）

A.若是司机责任，要求其全额赔偿

B.置之不理

C.向顾客道歉后，配合顾客进行修理

D.本地顾客可以不赔.外地顾客照价赔偿

什么是政府经济？如何理解政府经济？