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【多选题】
下面是测定化妆品pH的操作步骤，以下描述中，正确的是（）A.
称取定量样品于50ml烧杯，加入9倍重量的水，搅拌并加热至40℃使样品与水充分混合，冷却至室温，测定样品液温度
B.
按仪器要求准备pH计，并将温度补偿器调至样品液的温度
C.
预计样品的pH呈碱性，分别从标准磷酸缓冲液和硼酸缓冲液的试剂瓶中倒出约lOml溶液于小烧杯中反复校正pH计
D.
边搅拌边测定样品的pH，当读数稳定后，记录读数
E.
全部测定完毕后，按仪器要求，冲洗电极，并将甘汞电极的橡皮塞／帽套上，玻璃电极浸泡在纯水中，缓冲液倒回瓶中
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【单选题】听力原文：M: I bought a few books at the new bookstore. Would you like to have a look at them? W: A few? It looks like you bought out the bookstore. M: You really think so? I'll have to read them through i...
A.
She didn't like the books the man bought.
B.
There wasn't a large selection at the bookstore.
C.
The man bought a lot of books.
D.
She wanted to see what the man bought.
【单选题】The underlined words in the sentences below have at least two meanings. Look at how they are used and choose the correct meaning. The primary objective of the new legislation is to raise standards of ...
A.
most important or fundamental
B.
the name given to the education of children between the ages of five and 11
C.
medically, the beginning of growth or development
【简答题】________是顾客从拥有和使用产品中所获得的价值与为取得该产品所付出的成本之比.
【判断题】Jonas and Gabriel enjoyed themselves very much by meeting so many new things they never had the chances to look at in the community.
A.
正确
B.
错误
【简答题】________ 是顾客从拥有和使用产品中所获得的价值与为取得该产品所付出的成本之差。
【单选题】Some of the drawbacks of _____ test markets are that they can be very costly, and they can give competitors a chance to look at the company’s new ideas.
A.
standard
B.
controlled
C.
simulated
D.
Internet
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