分别画出与或非得逻辑符号，表达式

请问哪里能买到一些药品的标准品?我实验中要用到四环素、沙拉沙星、克伦特罗和酮洛芬几种药品的标准品或对照品,请问在哪里能买到啊?或者通过什么途径买到? 这如翻译：他们把已经批量过的产品当做标准品来卖 How old are you?i'm( ) (right)用一个字母进行调换,可以填进括号! We ****all at school yesterday. How old are you Iam right把 right换一个字母怎么换 We all ___ lectures at our school yesterday .We all ____ lectures at our school yesterday .A joined B took part in C oined in D attended选D为什么? we were _____ until 5.30 yesterday.(to school/at school) we did our homework at school yesterday.对at school 提问要对at school提问,没有evening 英语翻译句子有没有病子, 时态 CATHERINE :Has lan sold his house yet?CATHERINE :Has lan sold his house yet?一般过去式 还是 过去完成时? 九年级上册数学书第一章【证明（二）】习题1.2的第四题的第一小题,怎么写? 施工作业方法有几种?哪种作业最科学?为什么? The audience,___ high-school students,enjoyed the fashion show very much.a、most of whom are b、some of them are c、 most of whom is d、 some of them to be 如图AC为○o的直径弦BD于点E 试说明△ADE∽△BCE 如果AD^2=AE*AC说明CD=CB 27个正奇数的平均数,精确到0.1是15.9,精确到0.01是. 有23个奇数的平均数是15.4,这23个奇数的和是多少? motion detected是什么意思 motion sickness是什么意思 第一大题.第九小题. motion detector是什么意思 第一大题第九小题怎么写? circular motion是什么意思 motion 第七题第一小题,九题第一小题 王东是一个游泳爱好者,一天,他在河里游泳,逆流而上,途中不慎将游泳帽落入水中,游泳帽随河水漂流而下.过了8分钟后他发现游泳帽丢失了,立即返身往回游,问王东返回游了多长时间才追上他 还要在文中找到,★ Arriving in New York There are three airports in New York.When you arrive at one of them,you can take a bus or taxi to any place in New York.★ Public transport In New York there’s a good bus and subway service.If you are 科学作业A本七下答案 Cr y 什么意思 （用八上的知识解答）流体阻力的大小与运动物体的(),正()的大小,相对于流体的()大小以及流体的（）有关 开关CR什么意思 夸父逐日读音夸父的读音一直都是一个有争论有读(kuà fǔ)和(kuā fù)到底那个是正确的,一定要有依据, wo de shu ru fa mei le zen me ban