正确答案: C

．49

题目：从10名大学生毕业生中选3个人担任村长助理，则甲、乙至少有1人入选，而丙没有入选的不同选法的种数为【 】

解析：C

查看原题 点击获取本科目所有试题

举一反三的答案和解析：

[单选题]根据下面内容，回答 68~71题：DIt’s not easy being a teenager(13至19岁青少年)-nor is it easy being the parent of a teenager．You can make your child feel angry, hurt or misunderstood by what you say without realizing it yourself．It is important to give your child the space he needs to grow while gently letting him know that you’11 still be there for him when he needs you．Expect a lot from your child，just not everything．Except for health and safety problems， such as drug use or careless driving，consider everything else open to discussion．If your child is unwilling to discuss something，don’t insist he tell you what’s on his mind．The more you insist， the more likely that he’11 clam up．Instead，let him attempt to solve(解决)things by himself. At the same time，remind him that you’re always there for him should he seek advice or help．Show respect for your teenager’s privacy(隐私)．Never read his mail or listen in on personal conversations．

how to help a teenager grow up

[单选题]能鉴别Mg, AgNO3, Na2CO3,NaALO2，四种溶液的试剂是

HNO3

[单选题]应对气候变暖，关乎地球上每个国家和地区，关乎每一个人。33.早在1898年，就有科学家指出，燃烧煤炭和石油产生的二氧化碳将导致地球变暖。随后．

①②

[单选题]下列哪一条不是影响蒸发的因素（ ）。

液体黏度

[单选题]表面有双层膜包被。

叶绿体

[单选题]筛管分子间有穿孔相通，其中有联络索通过。( )

错误

[单选题]钢铁生锈过程发生如下反应：①2Fe+O2+2H2O=2Fe(OH)2；

反应①、②中电子转移数目相等

解析：①②反应中消耗O2的量相等，两个反应也仅有O2作为氧化剂，故转移电子数是相等的，A项正确。①中H2O的H、O两元素的化合价没有变，故不作氧化剂，B项错；铜和钢构成原电池，腐蚀速度加快，C项错；钢铁是铁和碳的混合物，在潮湿的空气的中易发生吸氧腐蚀，属于电化学腐蚀，故D项错。

[单选题]49_______

advice

解析：

根据后文的叙述可知，作者坚持完成了任务，所以本句句意应为“我尽力听从了她的建议，继续完成我的动作。” 故C项正确。