双硫腙比色法测定铅时，加人柠檬酸铵的目的（）。-我要搜题网

"The fundamental reasons why the electric car has not attained the popularity it deserves are the failure of the manufacturers to properly educate the general public regarding the wonderful utility of the electric; the failure of ’power companies’ to make it easy to own and operate the electric by an adequate distribution of charging and boosting stations. "
This quotation would hardly surprise anyone who follows electric vehicles. But it may be surprising to hear that in the year when it was written thousands of electric cars were produced and that year was nearly a century ago. This appeared in a 1916 issue of the journal Electrical World, which I found in Google Books, our searchable repository of millions of books. It may seem strange to look back a hundred years on a topic that is so contemporary, yet I often find that the past has valuable lessons for the future. In this case, I was lucky—electric
A. the topic he found in a book a century ago is so strange
B. he often finds that the past has valuable lessons for the future
C. there are many books on electric vehicles in the 20th century
D. books published before 1923 are in the public domain

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[单项选择]It was the summer of 1965. DeLuca, then 17, visited Peter Buck, a family friend. Buck asked DeLuca about his plans for the future. "I’m going to college, but I need a way to pay for it," DeLuca recalls saying. "Buck said, You should open a sandwich shop."
That afternoon, they agreed to be partners. And they set a goal. to open 32 stores in ten years. After doing some research, Buck wrote a check for $1000. DeLuca rented a storefront (店面) in Connecticut, and when they couldn’t cover their start-up costs, Buck kicked in another $1000.
But business didn’t go smoothly as they expected. DeLuca says, "After six months, we were doing poorly, but we didn’t know how badly, because we didn’t have any financial controls. " All he and Buck knew was that their sales were lower than their costs.
DeLuca was managing the store and going to the University of Bridgeport at the same time. Buck was working at his day job as a nuclear physicist in New York. They’d meet Monday evenings and br
A. It stood at an unfavorable palce
B. It lowered the prices to promote sales
C. It made no profits due to poor management
D. It lacked control over the quality of sandwiches

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[单项选择]下列各项，与瘰疬的病因病机无关的是（）
A. 心阳不足
B. 肝气郁结
C. 脾失健运
D. 肺阴不足
E. 肾阴亏虚

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[多项选择]收费“公告牌”上公示的内容包含（）。
A. 收费站名称
B. 审批机关
C. 收费单位
D. 收费起止年限

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[多选题]架空导线的线材应具备哪些特性( )。
A.具有良好的耐振性能,耐热性高,以提高输送容量
B.导电率高,以减少线路的电能损耗和电压降
C.机械强度高、弹性系数小
D.耐腐蚀性强,能够适应自然环境条件和一定的污秽环境,使用寿命长
E.重量轻、性能稳定、耐磨、价格低廉

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[判断题]接机人员应当至少在航空器入位前10分钟,对机位适用性进行检查。 ( )
A.正确
B.错误

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[单选题]主轴（）间隙过小，使摩擦力增加，摩擦热过多，造成主轴温度过高。
A.齿轮
B.轴承
C.回转
D.轴向

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[判断题]商业承兑汇票既可以由付款人签发，也可以由收款人签发，但银行承兑汇票只能由付款人签发。 ( )