方程x+y=6，x∈[3，4]和x=2+costy=3-sint(t为参数）对应

计算：2cos30°+sin45°-tan60°

一次数学抽测5位同学的成绩如下：100，98，97，95，34这组数据的平均数是______，中位数是______．

糖皮质激素是 （）

A.胆固醇衍生物

B.氨基酸衍生物

C.蛋白质衍生物

D.脂肪酸衍生物

E.多糖类物质

Looking back on my childhood, I am convinced that naturalists are born and not made. Although we were brought up in the same way, my brothers and sisters soon abandoned their pressed flowers and insects. Unlike them, I had no ear for music and languages. I was not an early reader and I could not do mental math.

Before World War I we spent out summer holidays in Hungary. I have only the dim(模糊的)memory of the house we lived in, of my room and my toys, Nor do I recall clearly the large family of grandparents, aunts, uncles and cousins who gathered next door. But I do have a crystal clear memory of dogs, the farm animals, the local birds and above all, the insects.

I am a naturalist, not a scientist. I have a strong love of the natural world, and my enthusiasm has led me into various investigations. I love discussing my favorite topics and enjoy burning the midnight oil reading about other people’s observations and discoveries.Then something happens that brings these observations together in my conscious mind. Suddenly you fancy you see the answer to the riddle. Because it all seems to fit together. This has resulted in my publishing 300 papers and books, which some may light honor, with the title of scientific research.

But curiosity, a keen eye ,a good memory and enjoyment of the animal and plant world do not make a scientist: one of the outstanding and essential qualities required is self-discipline, a quality I lack, A scientist can be made a naturalist. If you can combine the two, you get the best of both worlds.

小题1:According to the author, a born naturalist should first of all be      

A．full of ambition

B．self-disciplined

C．full of enthusiasm

D．knowledgeable小题2:The first paragraph tells us that the author    

A．lost his hearing when he was a child

B．didn’t like his brothers and sisters

C．was interested in flowers and insects in his childhood

D．was born to a naturalist’s family小题3:The author says that his a naturalist rather than a scientist probably because he thinks he    

A．just reads about other people’s observations and discoveries

B．lacks some of the qualities required of scientist

C．has a great deal of trouble doing mental arithmetic

D．comes up with solutions in most natural ways.小题4:The author can’t remember his clearly because    

A．He didn’t live very long with them

B．He was too young when he lived with them

C．The family was extremely large

D．He was fully occupied with observing nature小题5:Which of the following statements is true?

A．The author believes that a born naturalist cannot be a scientist

B．The author read a lot of books about the natural world and oil industry

C．The author’s brothers and sisters were good at music and languages

D．The author spent a lot of time working on riddles.

按照《五金交电家电化工商品的购销合同实施办法》规定，供方错发到站、中转单位、收货单位及接货人，与需方同城的，由需方就近解决。供方应承担（）。

A、违约金

B、货物损失

C、由此造成的损失和费用

D、中国人民银行规定的罚金