椭圆，e为离心率，p为一动点，PF1F2为直角三角形有几个,0<e<1

pm是什么时间 对自然数A.B,规定A#B=A\B*2+3求702#6的值是多少?若256#X=19求X的值 Excel2003里这样的时间如何转换?9/28/2010 12:43:50 PM转换成09/29/2010 00:43:50有如下两点注意：1,格式 9/5/2010 10:30:06 PM要求变为09/05/2010 22:302,9/28/2010 12:43:50 PM转换后应是09/29/2010 00:43:50 如下公式:=LEFT(A1, The shop is open at half past nine.这句话有错么? 中国有几大油田\在哪里我国最大的油田是什么油田,大庆油田、胜利油田、克拉玛依油田、中原油田,海上油田, 一个多边形截去一个角后,形成的多边形的内角和是2520度,那么原多边形的边数是 . 若10^(2n)-((8*10^n)-8)m是完全平方数,m和n能否都是正整数?说明理由 自然数A,B,规定A△B=A-B+2,如果(5△3)X=16,求X的值. 对自然数a,b规定a△b=a÷b×2+3 那么256△x=19 求x I think the shop is open now.同义句 PEP是什么意思啊?还有英语单词四会是什么意思 8A四会单词有哪些 当M为何值时,2^m*5^8是一位11位数的整数? 若整数N=2^m*5^8是一个10位数,试求m的所有可能取值 现在中国几大油田呢 我国第二大油田 方程x*x+y*y=n,x和y是未知数,n是给定的正整数,问（x,y）的正整数解的组数.注：（1,3）和（3,1）是两组解.1.我希望的答案是关于n的函数，并请您证明结论。(这是刚刚加上的，因为自己说的不清 对与非0自然数a b 规定a%b=a除于b乘2加3 且256%a=19 是几 通常的闹钟上都有60个表示分钟的标记,在0点至12点这12小时内,如果时针和分针指向两个相邻标记,那么应该是几点几分? have to be home 和 have to get home的区别十点之前必须到家是have to be home by 10 o'clock还是have to get home by 10 o'clock have to be home by 10 o'clock 为什么用by and i have to be in ____ by 10 pm I have to be home by 10:00pm.不应有at吗不应在home前加at吗?再说那我在家不是I'm at home. I will be allowed to have Monday ____ to go home用适当的介词或副词填(不好意思这题做不来, 中国第一个油田是什么油田? 小数报杯小小数学家考卷要历年决赛的 请教数学高手：已知月计划收入21万元,请问如何要根据一周不同收入比例,计算出日指标?例如8月份,周一至日比例分别为12%,11%,19%,11%,17%,10%,20%,周一至三分别为5天,周四至日分别为4天,怎样计算 两个单选题,英语,1.He gave me the phone number in order____contact him when we are in need of him when we are in need of help.A.to B .of me to C.for me to D.that I为什么选C呢?2.Is it any good_____ ______?A.to try; to explain B.to try; expl 帮我解答两个英语单选题!1.He like the painting very much ,which cost him $ 1,000.However ,he would gladly have paid twice as much for it .为什么选 c A.as much twice B.much as twice C.twice as much D.as twice much 2.I don’t deny that J 改错My father usually arrives at home at7：00 pmWhat a fine day Why not to go fishing with usWe walk through the bridge and have the meal under a big tree 两个英语单选题,1 --There are too many people in the museum during the National day--Yes,that is a serious threat to safety ___A___emergency.Ain case of B in defence of Cin need of D in search of2 Doctor Lin Qing ,___C___John turn to u for help 求问两道英语单选题,求详解,The man answered the phone in a loud voice at the meeting,made Andy annoyed．A．that B．what C．who D．whichI invited my parents to spend Christmas with us,but____of them came.A.none B.both C.either D.neithe