具养阴清肺、益胃生津功效的药物是（） A.黄精 B.石斛 C.百合 D.枸杞子 E.

设A=2a³+4a²﹣a﹣3，A+B=3a+4a³，则B=（    ）。

阅读下面有关“光合作用的发现”资料，分析回答下列问题：

资料一：1642年，布鲁塞尔的医生海尔蒙特把一株2.3kg重的柳树种在90.8kg的干土中，用雨水浇灌，5年后小柳树长成了重76.7kg的植株，而土壤重量仅比实验开始时减少57g．

资料二：1771年英国人普里斯特利发现将薄荷枝条和燃烧着的蜡烛放在一个密封的钟罩内，蜡烛不易熄灭；将小鼠与绿色植物放在同一钟罩内，小鼠也不易窒息死亡．接着，荷兰医生英格豪斯证实，植物只有在光下才能“净化”空气．于是，人们把1771年定为发现光合作用的年代．

资料三：1864年德国的萨克斯把一株盆栽植物放在黑暗处一昼夜，然后把其中一个叶片一半曝光、一半遮光，过一段时间后用碘蒸汽处理叶片，发现遮光那一半没有发生颜色的变化，曝光的那一面则成深蓝色．

（1）普里斯特利的实验有时成功，有时失败．在______条件下，实验会失败，这时钟罩内的蜡烛很快熄灭，小白鼠很快死亡的原因是______．

（2）萨克斯为何要将植物进行一昼夜的暗处理？答：______．

（3）海尔蒙特认为建造植物体的原料只是水．实际上，植物进行光合作用还需要另一种原料，请你像科学家一样，设计实验加以验证．你的实验方案是：______．

结论是：______．

根据《商业银行集团客户授信业务风险管理指引》，超过风险承受能力是指一家商业银行对单一集团客户授信总额超过商业银行资本余额( )以上或商业银行视为超过其风险承受能力的其他情况。

A．25%

B．15%

C．10%

D．8%

阅读理解

     The summer I was ten, my mother decided to bring us to the world of art. My brother and I were not

very excited when we realized what my mother meant. What she meant was not that we could take

drawing classes or painting classes but that we would have to spend one afternoon a week with her at

the Fine Arts Museum. Before each visit to the museum, she made us read about artists and painting

styles(风格). It was almost as bad as being in school. Who wants to spend the summer thinking about

artists when you could be with your friends at the swimming pool?

     First we had to read about ancient Egyptians(古埃及人) and their strange way of painting faces and

then go to look at them at the museum. My 12-year-old brother thought this was so funny, but I was not

interested. Later we had to learn about artists in the Middle Ages who painted people wearing strange

long clothing. We had to look at pictures of fat babies with wings and curly (鬈曲的) hair and with no

clothes on flying around the edges of paintings. I certainly couldn't see what was so great about art.

     On our last visit to the museum, something happened when I saw a painting by a woman called Mary.

In it, a woman was reading to a child. The colors were soft and gentle, and you could tell by the mother' s expression how happy she was just to be with the child. I couldn't stop looking at this painting ! I wanted

to see every painting Mary had ever made! It was really worth looking at so many paintings to find a

painter who could interest me so much.

1. The aim of the mother' s plan was to _________.

A. take them to visit the museum        

B. introduce them to the world of art

C. ask them to read about artists          

D. show them different painting styles

2. What was the writer' s experience in the museum before the last visit?

A. She came to feel her mother' s love.

B. She liked many paintings.

C. She hardly enjoyed herself.            

D. She could understand the pictures of fat babies.

3. What made the writer go through a change that summer?

A. One of Mary's paintings.              

B. A strange way of painting.

C. Artists in the Middle Ages.            

D. Her mother' s instruction.

4. From the text, we can see _________.

A. the importance of curiosity            

B. the effect of art

C. the value of learning                      

D. the power of family education

在一个码组中信息位为k位，附加的监督位为r位，则编码效率为（）。

A.r/r+k

B.1/r+k

C.k/r+k

D.r/k