高手帮忙,物理问题某雷达向外断续发射波长为20cm的电磁波,发射一次称一个脉冲,每个脉冲持续时间为0.02ms．则每个脉

I am allergic to such things as feathers and food made from poultry.

1碱基的排列顺序既决定生物的多样性也能决定同种生物间的多样性.当碱基的数目不同或碱基碱基的数目相同但各种碱基的数目不同时,肯定不是同种生物,此时决定的是生物体的多样性即物种的多样性.对同种生物而言,不同的个体的DNA分子的碱基排列顺序也是不同的.
2、精子和卵细胞的多样性决定了受精卵具有多样性,从分子水平上说也就是形成了不同基因型的受精卵,进而表现出不同的性状.

先用等热量法求有效电流,再求有效感应电动势

没什么影响.你是学分子的应该知道,没有effector是没有办法互作的.人体没有办法摄入转基因食品中的effector因为只是吃下去的而已,并且消化道中也没有受体,故没什么影响.

例如CH3COOH↔CH3COO- + H+
1.升高温度时正逆反应速率都应该比以前大呀 ? 对的
CH3COOH的浓度会减小 ,但也应该比升温前的大（只是速率大!）
速率大,不表示浓度大.（正逆速率都增大,浓度都增大?不可能的）
浓度变化取决于平衡移动方向.某物质生成的多,减小的少,浓度就增加了.同时速率是如何变化的是不知道的.方向取决于v（正）、v（逆）的大小.
v（正）> v（逆）,可能是都增大的（升温）,但前者增加的更多.一定正向移动
v（正）> v（逆）,可能是都减小的（降温）,但后者降低的更多.一定正向移动
升高温度时,平衡向右移动,为什么CH3COOH的浓度会减小呢?
你混淆了速率变化和平衡移动方向.
平衡移动方向取决于v（正）、v（逆）的相对大小
2.加入氢氧化钠溶液,CH3COOH与H+浓度都减小.
在CH3COOH↔CH3COO- + H+中电离程度约1%.99%是CH3COOH,1%是醋酸根离子.
加入少量NaOH,消耗一部分氢离子.但平衡还在.CH3COOH仍会大于氢离子的.
不懂请追问!

很欣赏楼主的用词和句式.这里有些纰漏需要指正.请鉴定.
第一行 fund不是表达丰富储备的意思,它是基金的意思,常用在财经领域.最好改为there is profound knowledge 或者there is a rich source of knowledge
第三行 promote the grade of culture 这里不是提升文化的等级,是提升学生的品位,动作的接受者不相符.最好改为 promote our quality of cultivation
build a nice atmosphere of culture in the school 一般来说是create a nice atmosphere of culture in the school
第三行 the reading day achieve complete success这是中式说法,对于英式讲法一般认为是人而不是物取得成功.最好改为complete success will be achieved on the reading day
希望能帮到你!

你得题很乱,看不明白

Please enjoy the third stage play.
Joyful time is always short.Today we see many students who show their courage and confidence on this stage.We hope to see more and more students in the later activities!That's the end of foreign language stage play competition.Thank you all!

一次最少x克,最多x+5克；一天最小剂量3x克,最大4（x+5）=4x+20克,相差x+20=25克,所以x=5,一次5-10克

How are binary nonmetal-nonmetal compounds named
译：两种非金属形成的化合物怎么命名?
Ans:put the element which has stronger oxidization(氧化性) behind the weaker one.
How are metal-nonmetal compounds named?
译：金属和非金属形成的化合物怎么命名?
Ans:put the metal element behind the nonmetal one.
Explain why it is necessary to use the prefixes mono(一),di（二）,tri（三）,etc.,more often for covalent(共价的) compounds than for ionic compounds .
Ans:because the covalent(共价的) compounds have many isomers（同分异构体）but ionic compounds don't have.
可以吗?

挂着上好的玉石,戴着像月亮一样闪光的珍珠.尽管有些无法理解的图案,我还是毫不灰心地骑马经过.
翻译一个句子往往是最难的.因为没有上下文.下次如果要翻译,请写出文字的出处.否则你很难得到想要的答案.

同位语就是并列关系
比如说:
The news that he died struck us .这里的news和he died 就是并列关系,消息的内容就是他死了.而that 就是起连接这两个关系的连词.这是一种情况.
还有一种就是职位,名称,头衔等的同位,比如说:
Mr Yu,the English teacher in our class,is very kind.
这句说明Mr Yu就是我们班的英语老师.是同位关系.
这你应该能懂吧,没懂就联系我,我再详细给你讲.

如F为关于x的多项式,用待定系数法,设x^k的系数为[a(k)],（[a(k)]代表的是k为a的下标,即数列形式的一组数的第k项.）
设F(x)= [a(n)]x^n + [a(n-1)]x^(n-1) + ...+ [a(1)]x + [a(0)]
x=1带入F(x)的表达式有：
F(1)=[a(n)]+ [a(n-1)] + ...+ [a(1)] + [a(0)] = ∑[a(n)] = 6 …………记为(1)
x=7带入F(x)的表达式有：
F(7)= [a(n)]*7^n + [a(n-1)]*7^(n-1) + ...+[a(2)]*7^2 + [a(1)]*7 + [a(0)]
=7{[a(n)]*7(n-1) + [a(n-1)]*7^(n-2) + ...+[a(2)]*7 + [a(1)]} + [a(0)]
=3438……………………记为(2)
而注意到3438=7*491 + 1
是不能被7除尽的,余数为1.所以可以知道[a(0)]除以7的余数为1
又由(1)式中∑[a(n)] = 6,而[a(n)]都是正整数,可以知道只能有：
【[a(0)]=1】
下面进一步计算：
[a(1)]+[a(2)]+...+[a(n)]=5
F(7)= [a(n)]*7^n + [a(n-1)]*7^(n-1) + ...+[a(2)]*7^2 + [a(1)]*7 + 1=3438
所以[a(n)]*7^n + [a(n-1)]*7^(n-1) + ...+[a(2)]*7^2 + [a(1)]*7 =3437
左右同时除以7：有 [a(n)]*7(n-1) + [a(n-1)]*7^(n-2) + ...+[a(2)]*7 + [a(1)] = 491 = 7*70 + 1
用与上面确定[a(0)]的相同的方法可以确定
【[a(1)]=1】
继续：
[a(2)]+...+[a(n)]=4
且[a(n)]*7(n-1) + [a(n-1)]*7^(n-2) + ...+[a(2)]*7 + 1= 491
所以[a(n)]*7(n-1) + [a(n-1)]*7^(n-2) + ...+[a(2)]*7=490
左右同时除以7：有[a(n)]*7(n-2) + [a(n-1)]*7^(n-3) + ...+[a(3)]*7 + [a(2)] = 70 = 7*10
那么判断出除去[a(2)]的其余项都是被7整除的,于是【[a(2)]=0】
继续：
[a(3)]+...+[a(n)]=4
[a(n)]*7(n-2) + [a(n-1)]*7^(n-3) + ...+[a(3)]*7 =70
两边同除7,[a(n)]*7(n-3) + [a(n-1)]*7^(n-4) + ...+[a(4)]*7 + [a(3)] = 10 =7+3
于是很显然【[a(3)]=3】
自然剩下一个大于3的某m 有[a(m)]=1,而其他项系数均为0.
至此,F可以表达为：【F(x)=[a(m)]*x^m + 3x^3 + x + 1】
再一次把7带入：F(7)=7^m + 3*7^3 + 7+ 1 = [a(m)]*7^m + 1037 = 3438
于是7^m = 2041,m=4
确定：
【F(x) = x^4 + 3x^3 + x +1】
x=3时
F(3)=3^4 + 3*3^4 +3 +1=166

两人相比,苹果一样多
小刚多买了3-1=2千克梨
小刚多花了56.4-44.4=12元
每千克梨:12÷2=6元
每千克苹果:(44.4-6)÷3=12.8元

5、不知道△p是什么,我猜是溶液上方水蒸气分压,那么请考虑引入的微粒数,显然尿素是最少的;
6、关键的地方看不到,到底做不做非体积功?我猜是不做;
15、只要定性考虑c和Kb的影响即可...铵根浓度大了水解平恒终态的H+不也大么...即c越大,酸性越强,然后Kb是描述碱性的,越大碱性越强,酸性越弱,pH与之正相关,注意这里是pKb...所以他还是-号...
16、我不明白你为什么算错...pOH=-lgKb(后面一截是0不用解释了吧...)=4.744,14一减即得9.255
18、简单计算一下就可以知道OH-的浓度是3.8*10^7,OH-比H+多,你说酸性还是碱性?
22、你可能缺少一个常识性的条件,浓度为多少可以认为沉淀完全?我们这边用的是10^6mol/L;
23、又有一个数看不到...我猜是1好吧..不知道你们老师是怎么教的,反正我高中老师是教我算被称为浓度商Q的一个玩意(就是像算K一样各种浓度相乘除),然后和K比较,就可以判断方向了,这一题你要把它的方程式看成两个子式的叠加就好理解了,方程式叠加K怎么算我就懒得说了.
24、ACD我知道有,B的话还真没见过,如果非要给理由我会说他的配体太多了,一个en就可以提供很多;
26、Kf*[M2+][X-]^4=[MX4]2-;
28和29完全是一回事...我想你可能比较不理解那个转移电子数n,注意,在计算过程中他们恰好被H+前面的系数次方消掉了.

1.look for-- find
2.likes--like.
3.hobbies--hobby或者是is --are
1.are--is
2.dinosaur --dinosaurs
3.fastly--fast或者quickly
1.去掉on
2.be--carry
3.cald--cold
1.likes--like
2.is --was
3.finded--found
1.is--are或者hobbies--hobby
2.shop--shopping
3.去掉was

it 指代前文同一个物的（单数）
that 指前文同类型事物（一般为单数）
they 指前文同一个复数
one 指前文人们或物
those 指代前文同一物复数 （那些）
these 指代前文同一物复数（这些）
要看语境

醉酒红尘多如梦
纵看浮世尽沧桑,
亦或：
醉酒红尘多如梦
魂起方忆世炎寒

我在你的卷子上直接作好了发你

look on /upon 旁观；观看
与(某人)同读(或合看)；同看(一本书等)：
看待；把…看做；视作(常与 as 连用)：
[亦作 look on to](场所、房间等)面向,朝向,面朝,面对

check up whether you have signed your name on your paper.

K=tan(a)
原式分子分母同时除以 cos(a),得到2*tan（a）-1/5+3*tan2（a）=3/11,
即可求得直线的斜率tan（a）=2.
得到斜率为2.

1 -1 1/2 -1/3
1 1 3 4

你是要翻译还是回答?

位移对时间的导数就是速度.速度对时间的导数是加速度.所以对位移求二阶导数得到的就是加速

这是3种不同的时态.第一句是现在完成时,表示“你已经看电影了吗?”“你是否看过这电影了?”强调的是如果看过了,就不用再看了.
第二句是一般过去式.只是想表明过去的一个事实.“你看了电影了?”
第三句是一般现在时.指的是“你看电影吗?”想知道你现在看还是不看.没有时间的差异.是问现在的状况.
不理解再追问啊.

加水后,Ag和Cl浓度是减小了,但是,H 和O离子浓度增大,始终成一个比例,他们只是改变离子个数,并没有改变它们的比例,能量是不会少的,离子也一样,化学变化只会改变他们的状态,并不能让他们凭空出现或消失

这个很容易啊,第一题的解题过程如下：2x-a＜1① x-2b＞3② 不等式①可看成：2x＜a+1③ (把小于号左边的-a移到右边,变成+a) 不等式②可看成：x＞3+2b④ (把大于号左边的-2b移到右边,变成+2b) 不等式①除以2得：x＜a/2+1/2⑤ 即：3+2b＜x＜a/2+1/2 因为 不等式组的解集为：-1＜x＜1 所以 3+2b=-1,a/2+1/2=1 解得：b=-2,a=1 所以 (a+1)(b-2)=(1+1)x(-2-2)=-8 第二题的解题过程如下：设有X个同学,则 5X+2-6（X-1）0 解得6

相交 因为a//b,a与c相交
平行 因为E为AB上任一点,过E点作ER//AD交DC于F所以EF//AD所以EF//BC

很高兴能为你解答
f（x）是奇函数,f（1）=0,所以f（-1）=0
若f（x）在（0,﹢∞）上增,则在（-∞,0）上增
所以f（x-1）

一表人才,人才济济,济济一堂
多此一举,一举成名,成名成家
满面春风,春风得意,得意门生
万众一心,一心一意,一意孤行

27kg尿素含有的氮元素质量 = 27*28/60 = 12.6kg
所以需要硝酸铵的质量 = 12.6/(28/80) = 36kg
即需要36千克硝酸铵.

(23)32 2^(2n-1)-1
(24)2
(25)C
(26)70
(27)466
(28)5
楼主..光要个答案没用啊..这些都是基础题我看一眼就做出来了,必须得自己弄懂,应付老师没用,不会的HI问我

Still clearly remembering,on April 6,2004,First time saw you,Is such sunlight,Lovable.That moment,I have then fallen in love with you,Is falls in love !1095 days and nights have passed,Although has laughs heartily also has the tears,But that has already become.Later road very is also long,I hope us to be able together diligently,Hand in hand walks together this whole life !

溴,碘离子分别被氯氧化成溴,碘单质
其在有机溶液中溶解度较大,能按显色来判别
碘单质为紫色,溴单质为棕红色

"nose around" 或 "nose about" 就是 to look for something kept private or secret,to pry into something,刻意去刺探他人隐私.譬如 The secretary nosed around her boss's desk to try and discover what was ha...

scisors 应该是scissors

1+2+3.+x（x为任何数）,这个是以1为首项,公差为1的等差数列,用求和公式就可以算出来.
3+4+5.+x,这个是以3为首项,公差为1的等差数列,用求和公式就可以算出来.
4+6+...x,这个是以4为首项,公差为2 的等差数列,用求和公式就可以算出来.
所以,先看数列是否为等差数列,然后找首项与项数,或者是首项与末项.利用求和公式来计算

1、（1）联立方程得：x=2a+1 y=2-a
因为x y>0
所以-1/2

My mother likes ping-pong and my father likes swimming.
She is seventy years old but she looks very young.

C
您先请的意思.
习惯用法
--这边请,布朗先生
--您先请.史密斯小姐
其它选项意思.
A 跟我走
B 你第一个

a^3+b^3+c^3-3abc
=(a+b)(a^2-ab+b^2)+c(c^2-3ab)
=(a+b)(a^2-ab+b^2)+c(c^2-3ab+a^2-ab+b^2-a^2+ab-b^2)
=(a+b)(a^2-ab+b^2)+c[(c^2-a^2-2ab-b^2)+(a^2-ab+b^2)]
=(a+b)(a^2-ab+b^2)+c[c^2-(a+b)^2]+c(a^2-ab+b^2)
=(a+b+c)(a^2-ab+b^2)+c(a+b+c)(c-a-b)
=(a+b+c)(a^2+b^2+c^2-ab-bc-ac)

正确.不需要

Spring FestivalThe Spring Festival is the most important festival for the Chinese people and is when all family members get together, just like Christmas in the West. All people living away from home go back, becoming the busiest time for transportation systems of about half a month from the Spring Festival. Airports, railway stations and long-distance bus stations are crowded with home returnees.
The Spring Festival falls on the 1st day of the 1st lunar month, often one month later than the Gregorian calendar. It originated in the Shang Dynasty (c. 1600 BC-c. 1100 BC) from the people's sacrifice to gods and ancestors at the end of an old year and the beginning of a new one.
Strictly speaking, the Spring Festival starts every year in the early days of the 12th lunar month and will last till the mid 1st lunar month of the next year. Of them, the most important days are Spring Festival Eve and the first three days. The Chinese government now stipulates people have seven days off for the Chinese Lunar New Year.
Many customs accompany the Spring Festival. Some are still followed today, but others have weakened.
On the 8th day of the 12th lunar month, many families make laba porridge, a delicious kind of porridge made with glutinous rice, millet, seeds of Job's tears, jujube berries, lotus seeds, beans, longan and gingko.
The 23rd day of the 12th lunar month is called Preliminary Eve. At this time, people offer sacrifice to the kitchen god. Now however, most families make delicious food to enjoy themselves.
After the Preliminary Eve, people begin preparing for the coming New Year. This is called "Seeing the New Year in".
Store owners are busy then as everybody goes out to purchase necessities for the New Year. Materials not only include edible oil, rice, flour, chicken, duck, fish and meat, but also fruit, candies and kinds of nuts. What's more, various decorations, new clothes and shoes for the children as well as gifts for the elderly, friends and relatives, are all on the list of purchasing.
Before the New Year comes, the people completely clean the indoors and outdoors of their homes as well as their clothes, bedclothes and all their utensils.
Then people begin decorating their clean rooms featuring an atmosphere of rejoicing and festivity. All the door panels will be pasted with Spring Festival couplets, highlighting Chinese calligraphy with black characters on red paper. The content varies from house owners' wishes for a bright future to good luck for the New Year. Also, pictures of the god of doors and wealth will be posted on front doors to ward off evil spirits and welcome peace and abundance.
The Chinese character "fu" (meaning blessing or happiness) is a must. The character put on paper can be pasted normally or upside down, for in Chinese the "reversed fu" is homophonic with "fu comes", both being pronounced as "fudaole." What's more, two big red lanterns can be raised on both sides of the front door. Red paper-cuttings can be seen on window glass and brightly colored New Year paintings with auspicious meanings may be put on the wall.
People attach great importance to Spring Festival Eve. At that time, all family members eat dinner together. The meal is more luxurious than usual. Dishes such as chicken, fish and bean curd cannot be excluded, for in Chinese, their pronunciations, respectively "ji", "yu" and "doufu," mean auspiciousness, abundance and richness. After the dinner, the whole family will sit together, chatting and watching TV. In recent years, the Spring Festival party broadcast on China Central Television Station (CCTV) is essential entertainment for the Chinese both at home and abroad. According to custom, each family will stay up to see the New Year in.
Waking up on New Year, everybody dresses up. First they extend greetings to their parents. Then each child will get money as a New Year gift, wrapped up in red paper. People in northern China will eat jiaozi, or dumplings, for breakfast, as they think "jiaozi" in sound means "bidding farewell to the old and ushering in the new". Also, the shape of the dumpling is like gold ingot from ancient China. So people eat them and wish for money and treasure.
Southern Chinese eat niangao (New Year cake made of glutinous rice flour) on this occasion, because as a homophone, niangao means "higher and higher, one year after another." The first five days after the Spring Festival are a good time for relatives, friends, and classmates as well as colleagues to exchange greetings, gifts and chat leisurely.
Burning fireworks was once the most typical custom on the Spring Festival. People thought the spluttering sound could help drive away evil spirits. However, such an activity was completely or partially forbidden in big cities once the government took security, noise and pollution factors into consideration. As a replacement, some buy tapes with firecracker sounds to listen to, some break little balloons to get the sound too, while others buy firecracker handicrafts to hang in the living room.
The lively atmosphere not only fills every household, but permeates to streets and lanes. A series of activities such as lion dancing, dragon lantern dancing, lantern festivals and temple fairs will be held for days. The Spring Festival then comes to an end when the Lantern Festival is finished.
China has 56 ethnic groups. Minorities celebrate their Spring Festival almost the same day as the Han people, and they have different customs.
I like to study in the library-我喜欢在图书馆读书

Every Sunday morning, I get up at five in order to find a seat in the library. I like the quiet atmosphere in the library, which makes me deeply absorbed in my study. Besides, there are reference books in the library which provide ready guidance to help me solve my problems. At home people come and go--some talking, others working. Inevitably, there are often noises around the house which make me nervous and unable to concentrate on my study. For the reasons mentioned above, I like to study in the library.
第二篇：
It seems that most students like to study in the library, especially when there are examinations. I also like to study in the library. Because of the quiet atmosphere, I can better concentrate on my study. The diligence of other people in the library also inspires me to work even harder. I usually get more by studying in the library. The library is a good place to study only if we observe its rules, such as not talking loudly. Otherwise the value of the library will be greatly reduced.
第三篇：
Generally speaking, a library is a very quiet place. In a library, I can better concentrate and study more effectively. Besides, there are all kinds of books, magazines and newspapers in a library which provide you with a great deal of useful knowledge. The library is a place where your desire for knowledge can be satisfied. Nor can one do research without the help of a library. When I was in college, every semester I Had to write several papers. It was the indispensable library that enabled me to do the necessary research and finish my papers in time. It is difficult to imagine what life would be like without library. We should try to keep our library such a good place that it is by obeying the library rules. We should try to make our library not only a source of knowledge but also a source of inspiration.

万事都要有个度,否则会陷入其中难以自拔

一种相似的方式被发现的影响与凋亡GSI这些事的癌症细胞凋亡Hoechst染色了33258想像存在凋亡细胞核.绝对正版.求积分

1 C or so是固定搭配,表示大约,左右的意思,句子意思就是说我的父母大约一年左右就会搬回小镇.
2 D 这是个强调句,it was not until…that…是个句型.
3 D 是个非谓语结构,表伴随.
因此我不赞成是A,B,D

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