已知角α的余弦线是单位长度的有向线段,则tanα=______.

题型:填空题

问题:

已知角α的余弦线是单位长度的有向线段,则tanα=______.

考点:任意角的三角函数
题型:填空题

It is not easy for people to sail (航海) around the world in quite small boats. Sometimes the weather gets bad. Accidents can happen easily and quickly.

One family once had an accident. A big fish swam under their boat and bit holes in it. Sea water came in and the boat soon went down. Luckily these people had another small boat——a lifeboat, so they all got into the lifeboat. They lived in the boat for many days. They ate and slept, and always hoped. At last people in a ship saved them.

How do people live in a very small lifeboat for a long time? They must be strong in every way, they must have a hope, and they must have a strong desire(愿望)to live. People cannot drink seawater. If they drink a lot of sea water, they will quickly die. They must catch rainwater and drink it. They must also catch fish and birds for food. Lifeboats do not often carry cookers. So people can not cook their food in the lifeboats. Raw (生的) fish and birds are not very nice but they are their only food. They must eat raw food, or they will die.

小题1:When the boat sank (下沉), the lifeboat gave the people _______.

A.food

B.beds

C.rainwater

D.hope小题2:One family once had an accident at sea, because _______.

A.their boat met bad weather

B.their boat hit a big rock and it was broken

C.nobody knew how to sail

D.a fish bit holes in their boat小题3: People can catch _______ for food and drink at sea in a lifeboat.

A. fish and birds                    B rainwater

C. both sea water and rainwater        D. both A and B

小题4:From the article (文章) we can know that ______.

A.It’s not interesting to sail around the world.

B.Fish in the sea are so dangerous.

C.we must have a strong desire(愿望)to live when we are in danger.

D.Nobody knows when we will die.

题型:填空题
阅读下列材料,回答问题。材料一 读下列图片并提取历史信息

图1 鸦片战争前中国的农村

图2  19世纪后期经营洋布的商铺

材料二 (明朝中后期)大户(机主)张机为生,小户(机工)赴织为活……听大户呼织,日取分金为饕餮计(生计)。
——蒋以化《西台漫记》
材料三 “(明政府规定)政府以钱粮、银两或预先购好的丝料分发机户,机户织毕交官取酬。但钱粮往往每发后期(延误时期),且多扣克。以浚削(剥削)之余,市腾踊(积压)之料。”“行货有税矣,而算及舟车;居货有税矣,而算及房舍。”
——《江苏省明清以来碑刻资料选集》及明史纪事本末
(1)图1反映了中国古代的哪种经济形态?它有哪些显著特点?图2反映的现象对图1中的经济结构有何影响?

______________________________________________________________________________________________________________________________________________________________

(2)根据材料二说明在城市的经济领域出现了什么新的现象?导致这一新现象出现的根本原因是什么?如何看待这种新现象的出现?

______________________________________________________________________________________________________________________________________________________________

(3)依据材料三并结合所学知识,指出导致材料二中出现的新的生产方式发展缓慢的原因。

______________________________________________________________________________________________________________________________________________________________

题型:填空题

价值工程所讲的“价值”是指()。

A.产品消耗的社会必要劳动时间 

B.成本与功能的比值 

C.功能与实现这个功能所耗费用的比值 

D.产品功能的实现程度

题型:填空题

下列关于《环境空气质量标准》中定义的叙述正确的是()。

A、TSP是指能悬浮在空气中,空气动力学当量直径≤25μm的颗粒物

B、环境空气质量标准主要分为四级

C、Pb是指存在于可吸入颗粒物中的铅及其化合物

D、氟化物是以气态和颗粒态形式存在的无机氟化物

题型:填空题

陕南民歌多有川楚之风,紫阳民歌和镇巴民歌已经列入中国国家级非物质文化遗产名录。

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