LB代表（）热电偶。A、镍铬-镍硅 B、镍铬-考铜 C、铂铑-铂 D、铂铑30-铂铑

透射原稿包括彩色负片、彩色反转片、彩色正片和（）底片。

仿照下面画线的句子，分别写两个句子，组成一段完整的话。

青春是一种令人艳羡的资本。凭着健壮的体魄，你可以支撑起一方蔚蓝的天空；________________，______________；________________，________________；凭着巨大的潜力，你可以变得出类拔萃，令人刮目。拥有青春，就拥有了一份潇洒和风流；_____________，________________；________________，________________。

Eating too much fatty food, exercising too little and smoking can raise your future risk of heart disease. But there is another factor that can cause your heart problems more immediately: the air you breathe.

Previous studies have linked high exposure (暴露）to environmental pollution to an increased risk of heart problem, but two analyses now show that poor air quality can lead to heart attack or stroke (中风）within as little as a few hours after exposure. In one review of the research, scientists found that people exposed to high levels of pollutants (污染物）were up to 5% more likely to suffer a heart attack within days of exposure than those with lower exposure. A separate study of stroke patients showed that even air that the U. S. Environmental Protection Agency (EPA) considers to be of “moderate” (良好）quality and relatively safe for our health can raise the risk of stroke as much as 34% within 12 to 14 hours of exposure.

The authors of both studies stress that these risks are relatively small for healthy people and certainly modest compared with other risk factors such as smoking and high blood pressure. However, it is important to be aware of these dangers because everyone is exposed to air pollution regardless of lifestyle choices. So stricter regulation by the EPA of pollutants may not only improve environmental air quality but could also become necessary to protect public health.

小题1:The text mainly discusses the relationship between       .   

A．heart problems and air quality

B．heart problems and exercising

C．heart problems and smoking

D．heart problems and fatty food小题2:The underlined word “modest” in Paragraph 3 most probably means   .

A．relatively high

B．extremely low

C．relatively low

D．extremely high小题3:What can we learn from the text?  

A．Eating fatty food has immediate effects on your heart.

B．The EPA conducted many studies on air quality.

C．Moderate air quality is more harmful than smoking,

D．Stricter regulations on pollutants should be made.小题4:The author’s purpose of writing the text is most likely to        .

A．inform

B．persuade

C．describe

D．entertain

某工程双代号网络计划如下图所示，图中已标㈩每个节点的最早时间和最迟时间，该计划表明（）。

A．工作1—3的最迟完成时间为8

B．工作4—7为关键工作

C．工作2—5的总时差为零

D．工作3—6的总时差为1

E．工作6—7的总时差为1

指数消弱定律