为把质量隐患消灭在萌芽状态，在( )的验收时应及时发现并处理不合格的施工质量。A．

序时平均数反映()。

A.同一时间不同现象的一般水平

B.同一时间同种现象的一般水平

C.不同时间不同现象的一般水平

D.不同时间同种现象的一般水平

阅读理解。

     Five million people visit Grand Canyon in the US every year. For the purpose of helping project Grand

Canyon for your fellow visitors and future generations, please follow the guidelines below. 

Camping 

     To project the park, camping is allowed only within permitted campgrounds. Permits are required for

overnight camping at the North Rim. Advance booking can be received by mail. Please write: Information

Center, P.O. Box 129, Grand Canyon, AZ 86023

Fires

     Because of the extreme fire danger, campfires are not allowed except at Mather and Desert View

campgrounds. Collection of firewood is not allowed either.

Hiking (远足)

     Please stay on permitted paths. Otherwise you may destroy desert plants. Pack out what you pack in,

so you leave no signs of your visit. It is important to keep in mind that you are in a national park where

wildlife exists.

Weather

     The weather at Grand Canyon can change very quickly. With so much rock, lightning (闪电) causes

a particular danger during sudden summer storms. These storms also frequently bring floods inside valleys,

a danger to hikers. Watch the skies and check daily weather reports.

Wildlife

     Do not feed park wildlife. There have been a few cases at Grand Canyon National Park where deer (鹿)

were purposely shot because they are plastic bags that left them sick and weak. Hungry deer can be danger

and have kicked and bitten visitors at Grand Canyon. Some other animals will also beg and bite. For your

own safety and the well-being of the animals, please do not feed wildlife, no matter how gentle they may

appear.

1. What can you do first if you want to go camping?

A. Know the permitted

B. Book campgrounds in advance

C. Make sure not to make a fire

D. Stop at Mather and Desert View

2. What do the underlined words "pack out what you pack in" in Paragraph 4 probably mean?

A. keep every out of campgrounds

B. take away everything you bring in

C. carry all the necessary food

D. look after your personal belongings

3. Why were some deer killed on purpose at Grand Canyon?

A. They ate wrong things and became very ill.

B. They were a danger to other gentle animals.

C. They begged food from visitors.

D. They kicked and bit visitors.

4. What is the main purpose of the text?

A. To provide travel information.

B. To report some recent news.

C. To teach tourists hiking skills.

D. To introduce the wild life.

产生运动性疲劳的重要因素是（）。

A.中枢神经变化

B.饮食情况变化

C.环境的适应

D.兴趣的增加

常见精神疾病的幻觉有哪些特点？

卤代烷与水作用，卤原子被羟基取代生成醇，这个反应叫卤代烷的（）。

A、水解

B、醇解

C、消除

D、氧化