公安行政强制执行主要包括( )。 A．强制拘留 B．强制传唤 C．遣送出境 D．强

阅读理解。

     Singapore, July 12－many people enjoy chewing (咀嚼) gum, but in 1992 Singapore decided to make it

against the law. The government said that people were not careful about throwing away used gum. Instead,

they dropped it on sidewalks and on the streets where it made a big mess. Chewing gum also got stuck in the

doors of the underground trains so that the doors didn't close properly. This meant the trains didn't run on time. Singapore said that people had to give up chewing gum or pay a lot of money to the government. During the

time without chewing gum, the streets and underground trains of Singapore were clean.

     Now the government of Singapore is changing the rules a little. Some dentists say that chewing sugarless

gum can help take care of people's teeth. Now the government says that people will be able to buy special

kinds of gum at drugstores for health reasons. Other kinds of gum are still not allowed.

 根据短文内容, 判断正(T)误(F).

(     )1. The text is probably taken from a story book.

(     )2. Chewing gum made Singapore dirty before 1992.

( )3. During the time without chewing gum, the streets and underground trains were clean.

( )4. People can buy special kinds of gum at the dentist's for health reasons.

( )5. Now in Singapore everyone can chew all kinds of gum freely.

哪一种是正常红细胞性贫血（）

A.再生障碍性贫血

B.海洋性贫血

C.铁粒幼细胞性贫血

D.缺铁性贫血

E.慢性疾病贫血

下图所示的实验组合,最终想证明的是

A．稀醋酸能使石蕊变红

B．二氧化碳和水都不能使石蕊变红

C．CO₂与H₂O反应的生成物是H₂CO₃

D．二氧化碳与水会反应，且生成物能使石蕊变红

移动式供气源4个气瓶允许每次更换（）个空瓶而不中断供气。

A、1

B、2

C、3

D、4

个体工商户使用全国统一的营业执照。