请画出抛在空中的排球受力示意图(不计空气阻力)

题型:操作题

问题:

请画出抛在空中的排球受力示意图(不计空气阻力)

考点:力的示意图重力的示意图
题型:操作题

课外说明文阅读

  绿色植物是吸收二氧化破、制造氧气的天然加工厂。人和动物要不断呼吸,吸进氧气,呼出二氧化碳;各种燃料燃烧也要放出大量二氧化碳,当空气中的二氧化碳增加到一定浓度时,人就会感到头痛耳鸣、恶心呕吐,血压增高。但你不必担心空气中氧气会越来越少,二氧化碳会越来越多,因为绿色植物能够吸收二氧化碳,放出氧气,使大气中二氧化碳和氧气的含量保持相对恒定。据测定,每15亩绿地每天能吸收900公斤二氧化碳,产生600公斤氧气。

  绿色植物是天然的空气调节器和净化器。绿色植物能调节小气候。夏天,绿化地带的温度比非绿化地带要低1-3度;冬天,绿化地带温度又比非绿化地带高0.1-1度。灰尘、工业粉尘对人体健康危害不小,能引起支气管炎、哮喘、肺炎、矽肺等病,绿色植物是吸附灰尘的能手。据测定,在绿化地带空气中灰尘的含量比非绿化地带要减少一半以上。不少绿色植物还能放出一股芬芳的气味,其中含有植物杀菌素,能够杀灭大量细菌,如香樟、桉树、柏树、衫木、夹竹桃等都能分泌杀菌素。而且许多绿色植物吸附有害有毒气体,如松树、柑橘能吸收二氧化硫,夹竹桃、香樟能吸收汽车废气。

1、文中两次出现“据测定”,能否删去,为什么?

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2、全文说明的内容是什么?请用一句话概括。

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3、请你拟一条有关绿色环保的公益广告语。(语言要精练得体)

例l:踏破青毡可惜,多行数步何妨。

例2:春花烂漫,请您手下留情。

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题型:操作题

汽车的技术状况是指评价时刻,汽车的外观和()的总和。

A.发动机性能

B.底盘性能

C.尾气排放量

D.性能参数值

题型:操作题

What’s in a surname You may ask. A new website project has been released, that helps you (1) . Have you ever wondered why your ancestors gathered where they did, or where others with your surname live now A research project (2) in Britain answers these questions. And another study has found the surnames are (3) .
"Smith", for example, remains the most common surname in Britain. Used by (4) people, it has exactly the same concentration it always did in Lerwick, in the Scottish Shetland Islands. "Jones" is (5) , and is the most common among hill farmers (6) .
The data used for this project comes partly (7) . A number of other files are held by Expairing, which is probably Britain’s (8) .
There’ re some of us who are fairly predictable. "Campbell", for example, as you might expect, is somewhat concentrated (9) , and it appears really bizarre to be found anywhere else.
Well, with 25,000 names as (10) , what you can do is put them in general categories, if, for example, you look at (11) . Like the name Webber, you might find it is much more common in the Midlands than (12) . If you go to Wales, most people get their names (13) . And in Yorkshire for example, a lot of people have names (14) that they originally lived in or at least their ancestors did.
Well, we only have 25, 000 names on this website, but there’re (15) now found in Britain and they’ re particularly interesting, for (16) . Most British names are fairly common. And about what we can now do as such is look for (17) from different parts of the world and different faiths, (18) . And what there is in names is actually extremely useful, for researchers in (19) may find a lot about (20) now living in this country.

What’s in a surname You may ask. A new website project has been released, that helps you (1) . Have you ever wondered why your ancestors gathered where they did, or where others with your surname live now A research project (2) in Britain answers these questions. And another study has found the surnames are (3) .
"Smith", for example, remains the most common surname in Britain. Used by (4) people, it has exactly the same concentration it always did in Lerwick, in the Scottish Shetland Islands. "Jones" is (5) , and is the most common among hill farmers (6) .
The data used for this project comes partly (7) . A number of other files are held by Expairing, which is probably Britain’s (8) .
There’ re some of us who are fairly predictable. "Campbell", for example, as you might expect, is somewhat concentrated (9) , and it appears really bizarre to be found anywhere else.
Well, with 25,000 names as (10) , what you can do is put them in general categories, if, for example, you look at (11) . Like the name Webber, you might find it is much more common in the Midlands than (12) . If you go to Wales, most people get their names (13) . And in Yorkshire for example, a lot of people have names (14) that they originally lived in or at least their ancestors did.
Well, we only have 25, 000 names on this website, but there’re (15) now found in Britain and they’ re particularly interesting, for (16) . Most British names are fairly common. And about what we can now do as such is look for (17) from different parts of the world and different faiths, (18) . And what there is in names is actually extremely useful, for researchers in (19) may find a lot about (20) now living in this country.

题型:操作题

以下可以看做是科学的是()。

A.知识实体

B.获得知识的方法

C.前两项

题型:操作题

在国网公司的施工分包安全管理规定中,劳务分包商必须具备相应的()条件。

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