he的复数形式

波长与颜色为什么单纯的某个波长的光是一个颜色,另外两种波长的光按一定比例混合后也可以呈这种颜色?比如,紫光波长比红、蓝光都短,但红、蓝光混合后却呈紫色?还有,为什么光的三基色 l,my,has,brother,a,ball,soccer,but,don't Children用does还是do啊?my brother? 英语语法,是I run faster than my brother还是I run faster than my brother doesI run faster than my brother does肯定是对的，但是I run faster than my brother我也见到过， 已知数列an的前n项和为sn,且对任意正整数n都有an是n与sn的等差中项(1)bn=an+1,求bn 已知数列｛an｝的前n项和为Sn,且对任意正整数n都有an是n与Sn的等差中项.（1）若bn=an+1,求数列｛bn｝的通项公式.（2）若cn=2n+1/bn,数列｛cn｝的前n项和为Tn,求证：Tn (a b c)*(a平方 b平方 c平方-ac-bc-ca）有没有简便方法 i am going to be late for school .there are _____buese on this routea too few b too litte c too many d too much 一般人解不出来过点P(a,b)作两条直线l1,l2,斜率分别为1,-1,已知l1与圆o1：（x+2）^2+（y-2）^2=2交于不同的两点AB,l2与圆o2：（x-3）^2+（y-4）^2=2交于不同两点CD,且|AB|=|CD|、（1）求a,b满足的约束条件 没有人会解? 一道至今没人解出来的题!有二十四个点,把这些点用直线连起来,点和点不能交叉,线不能重合,不能斜着画( / )我每次连都只有一个空着,一个都不能少啊!示意图:.....只有二十四个点那- -你的图 有没有人解出七桥问题 1.The key to the success of any film is finding a capable and qualified artistic director,_____I always hope to be.A.who B.that C.what D.which D (为什么不选A）2.I gave that boy so difficult a math problem ____ he couldn’t work out.A.that B.wh (请解释明白选正确答案的原因,以及错误选项的原因)谢谢!--Does your car require______,sir?--Yes.I require that it _____right now.A.washing; is washed B.being washed; be washed C.to be washed; is washed D.washing; be washed i’m going to m_____to a new school空格里填什么 将7.8gNA2O2溶解在92.2g水中,所得的溶液中溶质的质量分数是多少? And l just want you to know,I'm here for you.中文意思是什么 Look at these three groups of letters.They get together in the same way.Please put letters Q,X and Z in the proper blanks.1.H I O ( ) 2.N S ( ) 3.J L G ( ) 人解决问题的思维过程 Love is really not a good thing really good hobby love 的意思?急、 I really good love you,Unfortunately,you do not understand me 把函数周期缩小一半,怎么算?帮我看看这题!f(x)=(cos2wx+sin2wx+1)/2,把周期缩小一半, 周期函数,5,6题 有没人会解这题 怎么都没有人解我的题? 有没有人会解这道题2000 dC/dt =x/60-7.2CC（0）=0 u should love the person that makes u glad that u r alive 是哪首歌歌词?RT 翻译成中文 That person should not be l,should be the human who you most love 高中英语语法单选题-You just think of yourself!You kept me waiting for about 2 hours.-I am very sorry that you______ think so.A could B would C should D might答案应该选C,想问这里为什么用should, 高中英语语法单选题 (1)—how long do you support it__he arrived here.—No more than half a week A.when B.before C.after D.since 正解为D,why还有after为什么不行(2)—Has the boy who was made__use of realized his mistakes.A.stealing 根据含碳物质的衍变填答：（1）碳的两种氧化物的化学式及碳的化合价分别是①_____________；②______________.（2）完成下列化学方程式：①____________________；②____________________；③__________________