我有几道数学题不懂，想请教你们，是职高的数学，希望能够告诉我，谢谢1.高一（5）班48名学生参加期末测试，语文、数学、英语三门课成绩不及格的学生人数如下表，是根据所给信息推算出48位学生中都及格的学生。
不及格科目 语文 数学 英语 语文、数学 数学、英语 语文、英语 语文、数学、英语 不及格人数 8 11 15 4 8 6 3 2.某工厂生产的产品每件单价为80元，生产成本是60元，该厂每月其他开支是5000元，如果该工厂计划每月至少获得200000元利润，假定生产的全部产品都能卖出，问每月的产量至少是多少？ 3.数学老师既聪明又风趣，经常和学生一起做数学游戏，使他们开动脑筋有开发思维，同学们都喜欢和他在一起玩。“你今年多大了？”调皮的“超人”问老师，“我想你这么大时，你才出生，你到我这没大时，我都37岁了。”老师回答说，这下子把“超人”给唬住了，抓破了头皮也想不出答案，你能帮他一把，行吗？ 4.一个矩形的周长是100cm，对角线长时x，试把矩形的面积表示为x的函数。 5.一桶盐水200千克，含盐率10%，要使含盐率达到10%，要蒸发掉多少千克？ 6.蜥蜴体长10cm长时，体重 15克，当它长到20cm长时体重多少？ 7.已知两个数的最大公因数为4，最小公倍数为120，求这两个数？ 就这些题，每道题都要有解题过程，谢谢
第2题设未知数x可得80x减60x再减5000等于200000解得10250 第三题可设两人年龄之差为x老师年龄为y由题可知该生年龄为x可列出x加y等于37;y减x等于x减0解得y等于24.6约25 后几题见下帖
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扫描下载二维码谁能给几道经典高中英语或数学题,有答案和解释,谢谢麻烦给几道经典高中英语或数学题,有答案和解释,谢谢
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5 在长方体ABCD—A1B1C1D1中,AB=4,BC=3,CC1=2,如图 (1)求证 平面A1BC1∥平面ACD1；(2)求(1)中两个平行平面间的距离；(3)求点B1到平面A1BC1的距离 6 已知正四棱柱ABCD—A1B1C1D1,点E在棱D1D上,截面EAC∥D1B且面EAC与底面ABCD所成的角为45°,AB=a,求 (1)截面EAC的面积；(2)异面直线A1B1与AC之间的距离；(3)三棱锥B1—EAC的体积 7 如图,已知三棱柱A1B1C1—ABC的底面是边长为2的正三角形,侧棱A1A与AB、AC均成45°角,且A1E⊥B1B于E,A1F⊥CC1于F (1)求点A到平面B1BCC1的距离；(2)当AA1多长时,点A1到平面ABC与平面B1BCC1的距离相等 8 如图,在梯形ABCD中,AD∥BC,∠ABC= ,AB= AD=a,∠ADC=arccos ,PA⊥面ABCD且PA=a (1)求异面直线AD与PC间的距离；(2)在线段AD上是否存在一点F,使点A到平面PCF的距离为 参考答案 5 (1)证明 由于BC1∥AD1,则BC1∥平面ACD1同理,A1B∥平面ACD1,则平面A1BC1∥平面ACD1(2)解 设两平行平面A1BC1与ACD1间的距离为d,则d等于D1到平面A1BC1的距离 易求A1C1=5,A1B=2 ,BC1= ,则cosA1BC1= ,则sinA1BC1= ,则S = ,由于 ,则 S ·d= ·BB1,代入求得d= ,即两平行平面间的距离为 (3)解 由于线段B1D1被平面A1BC1所平分,则B1、D1到平面A1BC1的距离相等,则由(2)知点B1到平面A1BC1的距离等于 6 解 (1)连结DB交AC于O,连结EO,∵底面ABCD是正方形∴DO⊥AC,又ED⊥面ABCD∴EO⊥AC,即∠EOD=45°又DO= a,AC= a,EO= =a,∴S△EAC= a(2)∵A1A⊥底面ABCD,∴A1A⊥AC,又A1A⊥A1B1∴A1A是异面直线A1B1与AC间的公垂线又EO∥BD1,O为BD中点,∴D1B=2EO=2a∴D1D= a,∴A1B1与AC距离为 a(3)连结B1D交D1B于P,交EO于Q,推证出B1D⊥面EAC∴B1Q是三棱锥B1—EAC的高,得B1Q= a7 解 (1)∵BB1⊥A1E,CC1⊥A1F,BB1∥CC1∴BB1⊥平面A1EF即面A1EF⊥面BB1C1C在Rt△A1EB1中,∵∠A1B1E=45°,A1B1=a∴A1E= a,同理A1F= a,又EF=a,∴A1E= a同理A1F= a,又EF=a∴△EA1F为等腰直角三角形,∠EA1F=90°过A1作A1N⊥EF,则N为EF中点,且A1N⊥平面BCC1B1即A1N为点A1到平面BCC1B1的距离∴A1N= 又∵AA1∥面BCC1B,A到平面BCC1B1的距离为 ∴a=2,∴所求距离为2(2)设BC、B1C1的中点分别为D、D1,连结AD、DD1和A1D1,则DD1必过点N,易证ADD1A1为平行四边形 ∵B1C1⊥D1D,B1C1⊥A1N∴B1C1⊥平面ADD1A1∴BC⊥平面ADD1A1得平面ABC⊥平面ADD1A1,过A1作A1M⊥平面ABC,交AD于M,若A1M=A1N,又∠A1AM=∠A1D1N,∠AMA1=∠A1ND1=90°∴△AMA1≌△A1ND1,∴AA1=A1D1= ,即当AA1= 时满足条件 8 解 (1)∵BC∥AD,BC 面PBC,∴AD∥面PBC从而AD与PC间的距离就是直线AD与平面PBC间的距离 过A作AE⊥PB,又AE⊥BC∴AE⊥平面PBC,AE为所求 在等腰直角三角形PAB中,PA=AB=a∴AE= a(2)作CM∥AB,由已知cosADC= ∴tanADC= ,即CM= DM∴ABCM为正方形,AC= a,PC= a过A作AH⊥PC,在Rt△PAC中,得AH= 下面在AD上找一点F,使PC⊥CF取MD中点F,△ACM、△FCM均为等腰直角三角形∴∠ACM+∠FCM=45°+45°=90°∴FC⊥AC,即FC⊥PC∴在AD上存在满足条件的点F
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扫描下载二维码求几道高一英语题的解.谢谢了,大神帮忙啊请把下列各题的主语改为第三人称单数. 1.I go to school and come home a bicycie every day. 2.I wash my hands before I eat someting. 8.I don't know her very well. 4.I always try my best when I am told to do something 给下列题改错. 1.How is jane yesterday? 2.He go to school by bus last week. 3.He often goes home at 6:00 last month. 4.I can fly kites seven years ago. 5.Did you saw him just now. 6.Tom wasn't watch TV last night. 7.I didn't my homework yesterday. 8.He wait for you three hours ago. 9.Who find it just now?
请把下列各题的主语改为第三人称单数.1.He goes to school and comes home by bicycie every day.2.She washes her hands before she eats someting.3.He doesn't know her very well.4.She always tries her best when she is told to do something 给下列题改错.1.How was jane yesterday?2.He went to school by bus last week.3.He often went home at 6:00 last month.4.I could fly kites seven years ago.5.Did you see him just now.6.Tom wasn't watching TV last night.7.I didn't do my homework yesterday.8.He waited for you three hours ago.9.Who found it just now?
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扫描下载二维码几道英语题目高一难度1.你把所有的数加起来就会知道结果.（add up）2.我们很努力想让他平静下来,但他还是激动地大叫.（calm down）3.玛丽在医院里住了很长的一段时间后,恢复了健康.（recover）4.李鸣在这里定居后,和邻居们相处得很好.（settle；get along with）5.如果你不想和我在一起,你就收拾东西走人.（pack up）6.战争期间,我受了很多苦.我用日记记下自己的经历,以便老了以后能够记住.（suffer；set down）要人工的翻译,用括号里的词.刚刚发了次扣了我分没出问题,会答的追100分.4楼的用自动翻译的，还说累死？搞笑！
【爵爷】0085
.If you add up all numbers and then will know a result.(Add up)2.We would like to let him calm down,but he alsoshout loudly and excitedly .3.After lived in the hospital for a long period of time,Mary recovered a health.4.After here settle down,LiMing gets along with the neighbors very good.(SGet along with)5.If you don't want to live with me together,you pack up thing to leave.6.During the war,I was suffered to a lot of bitternesses.I set down an own career with the diary,in order to old hereafter can remember.(SSet down)
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