因式分解: (1)﹣2xy﹣x2﹣y2; (2)16(m﹣n)2﹣9(m+n)2

题型:计算题

问题:

因式分解:

(1)﹣2xy﹣x2﹣y2

(2)16(m﹣n)2﹣9(m+n)2

(3) 4x2(x﹣y)+(y﹣x).

考点:因式分解
题型:计算题

(14分)金刚烷是一种重要的化工原料,工业上可通过下列途径制备:

请回答下列问题:(1)     环戊二烯分子中最多有____________个原子共平面;

(2)     金刚烷的分子式为_______________,其分子中的CH基团有_____________个;

(3)     下面是以环戊烷为原料制备环戊二烯的合成路线:

其中,反应②的反应试剂和反应条件_____________,反应③的反应类型是___________;

(4)A是二聚环戊二烯的同分异构体,A分子结构中有一个甲基,A能使溴的四氯化碳溶液褪色,A经高锰酸钾酸性溶液加热氧化可以得到对苯二甲酸【提示:苯环上的烷基(一CH3,一CH2R,一CHR2)或烯基侧链经高锰酸钾酸性溶液氧化得羧基】,写出A所有可能的结构简式(不考虑立体异构):                                                        

题型:计算题

儿枕痛为()

A.产后小便淋漓涩痛

B.产后头枕部疼痛

C.产后身痛

D.妊娠腹痛

E.产后腹痛

题型:计算题

利用世行贷款建设的公路工程,选择监理队伍必须采用( )。

A.国内竞争性招标

B.国际竞争性招标

C.国内有限招标

D.国际有限招标

题型:计算题

Melissa and LoveLetter made use of the trust that exists between friends or colleagues. Imagine receiving an (6) from a friend who asks you to open it. This is what happens with Melissa and several other similar email (7) . Upon running, such worms usually proceed to send themselves out to email addresses from the victim’s address book, previous emails, web pages (8) .

As administrators seek to block dangerous email attachments through the recognition of well-known (9) , virus writers use other extensions to circumvent such protection. Executable (.exe) files are renamed to .bat and .cmd plus a whole list of other extensions and will still run and successfully infect target users.Frequently, hackers try to penetrate networks by sending an attachment that looks like a flash movie, which, while displaying some cute animation, simultaneously runs commands in the background to steal your passwords and give the (10) access to your network.

6()

A.attachment

B.packet

C.datagram

D.message

题型:计算题

男性,52岁,因独饮白酒500g后约4h家人发现其神志不清、呕吐而急诊。患者既往体健。查体:神志模糊,面色潮红,BP:136/85mmHg,T:38.7℃,P:122次/分,R:24次/分,呼出气有酒味。颈软,两肺闻及湿啰音及少量干啰音,肺心(-),腹部(-)。拟诊"急性酒精中毒、吸入性肺炎"。患者经皮试阴性后在应用头孢哌酮/舒巴坦(舒普深)抗感染治疗中,突发多汗、面色潮红、心率达150次/分钟,血压下降80/52mmHg,最可能的是()

A.过敏性休克

B.双硫醒反应

C.感染性休克

D.低血糖反应

E.急性心力衰竭

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