改革开放，被称为我国农民的三大历史性创造是（），（）和（）

期货公司在与客户订立期货经纪合同时，未提示客户注意《期货交易风险说明书》内容，并由客户签字或者盖章，对于客户在交易中的损失，应当依据合同法的规定承担相应的赔偿责任。但是，根据以往交易结果记载，证明客户已有交易经历的，应当免除期货公司的责任。（）

已婚女性，47岁，孕3产1。因月经紊乱伴经量增多6月于2010年7月20日就诊。既往月经4~5天/28～32天，现月经7～10天/15~45天，LMP2010-7-18，量多有血凝块。查轻度贫血貌，全身皮肤黏膜无出血点和淤斑。子宫略增大，双附件未扪及异常。

子宫附件B超提示子宫浆膜下见直径约3cm的低回声包块。下一步做哪种检查（）

A.诊断性刮宫术

B.分段诊断性刮宫术

C.尿妊娠试验

D.性激素检查

E.盆腔CT检查

F.凝血功能检查

阅读理解。

     Harvard researchers have created a tough, low-cost, biodegradable (可生物降解的) material

inspired by insects' hard outer shells. The material's inventors say it has a number of possible uses and

someday could provide a more environmentally friendly alternative to plastic. The material, made from

shrimp (虾) shells and proteins produced from silk, is called "shrilk." It is thin, clear, flexible and strong.

     A major benefit of the material is its biodegradability. Plastic's toughness and flexibility represented a

revolution in materials science during the 1950s and '60s. Decades later, however, plastic's very

durability (耐用性) is raising questions about how appropriate it is for one-time products such as plastic

bags, or short-lived consumer goods, used in the home for a few years and then cast into a landfill where

they will degrade for centuries. What is the point of making something that lasts 1,000 years?

     Shrilk not only will degrade in a landfill, but its basic components are used as fertilizer (肥料), and so

will enrich the soil.

     Shrilk has great potential, the inventors said. Materials from which it is made are plentiful in nature,

found in everything ranging from shrimp shells, insect bodies to living plants. That makes shrilk low cost,

and its mass production possible should it be used for products demanding a lot of material.

     Work on shrilk is continuing in the lab. The inventors said the material becomes flexible when wet, so

they're exploring ways to use it in wet environments. They're also developing simpler production

processes, which could be used for non-medical products, like for computer cases and other products

inside the home. They're even exploring combining it with other materials, like carbon fibers, to give it

new properties.

1. Paragraph 1 of the passage is mainly about shrilk's _________.

A. remarkable design

B. interesting name

C. major features

D. basic elements

2. What has become a concern about plastic?

A. Using it properly.

B. Producing it cheaply.

C. Developing its properties quickly.

D. Evaluating its contributions fairly.

3. According to the inventors, shrilk has great potential partly because _________.

A. it can help plastic degrade

B. it can be found in living things

C. its mass production has been realized

D. its raw materials are abundant in nature

4. What are the inventors doing in the lab?

A. Replacing carbon fibers with shrilk.

B. Testing shrilk's use in wet conditions.

C. Making shrilk out of used household goods.

D. Improving shrilk's flexibility for medical purposes.

5. Which of the following can be the best title for the passage? 

A. Recent Progress in Environmental Protection

B. Benefits of Insects in Scientific Research

C. The Harm of One-time Products

D. A Possible Alternative to Plastic

当伤者牙关紧闭，无法进行口对口人工呼吸时，应（）。

A、用工具把嘴撬开

B、加大压力口对口吹气

C、口对鼻吹气

在电力机车上主要有几种电阻？