中国大学MOOC: 在图2电路中，保证电路执行非门操作，输入信号A为逻辑低电平“0”，输出F为逻辑“1”时，信号B、D应该是 。http://edu-image.nosdn.127.net/9C8977A74B2C6B852C49D4E0E2D4324A.jpg?imageView&thumbnail=890x0&quality=100

中国大学MOOC: 下列取代羧酸中酸性最强的是（）。http://edu-image.nosdn.127.net/7C237BDF245EC393A5506C4874523609.png?imageView&thumbnail=890x0&quality=100、http://edu-image.nosdn.127.net/EFA954264582A372C3C9085E40BE80E9.png?imageView&thumbnail=890x0&quality=100、http://edu-image.nosdn.127.net/926CD4F17B92218A7FF5D06D34C5CAAF.png?imageView&thumbnail=890x0&quality=100、http://edu-image.nosdn.127.net/6504083F25D32BC8A95C11AC770935E2.png?imageView&thumbnail=890x0&quality=100

中国大学MOOC: 若第9题中当电路中总电压http://edu-image.nosdn.127.net/45D53DF610EBF196EBE5238589C91ABF.png?imageView&thumbnail=890x0&quality=100，http://edu-image.nosdn.127.net/8232D55E2C1346F746EFBB0780167F51.png?imageView&thumbnail=890x0&quality=100，http://edu-image.nosdn.127.net/A2CC3366BF7376F66D8EFFEB40B97149.png?imageView&thumbnail=890x0&quality=100，以下叙述正确的是

已知图示有压混联输水管路（按长管计）各管段的沿程阻力系数http://edu-image.nosdn.127.net/1443EEDD6C2FA09BB126BDB9642044BA.png?imageView&thumbnail=890x0&quality=100，管径http://edu-image.nosdn.127.net/974CD2163F1D3BFAAEDC8DA84872F1CA.png?imageView&thumbnail=890x0&quality=100，管长http://edu-image.nosdn.127.net/76A594A1299928A8955B35FC20252D31.png?imageView&thumbnail=890x0&quality=100，流量http://edu-image.nosdn.127.net/1D52DAEDDD85EC829BD9C6E6F96AE143.png?imageView&thumbnail=890x0&quality=100,,则http://edu-image.nosdn.127.net/DAC36D2F41C6C3F84F776BC849094BA1.png?imageView&thumbnail=890x0&quality=100中k=（ ）。http://edu-image.nosdn.127.net/06283F2B8E549ACD83D8DDBBD7E4BE7C.png?imageView&thumbnail=890x0&quality=100

http://edu-image.nosdn.127.net/EC9D7EA61F1EFFB86E66B5E0259BCBBD.png?imageView&thumbnail=890x0&quality=100http://edu-image.nosdn.127.net/13F84D3AF06E795D4BF13D9C8B0AD44F.png?imageView&thumbnail=890x0&quality=100