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问题 选择题

已知集合M={0，1，2，3}，N={1，3，5}，P=M∩N，则P的真子集共有（　　）

A．2个

B．3个

C．4个

D．7个

答案

∵集合M={0，1，2，3}，N={1，3，5}，

∴P=M∩N={1，3}，

则集合P的真子集的个数为22-1=3个．

故选B

听力题

Visitors to Britain may find the best place to enjoy local culture is in a traditional pub(酒吧). A team of researchers have revealed(揭示) some of ____小题1:____ unknown culture of British pubs --- starting with the difficulty of getting a drink. This may sound inconvenient, but there is a ____小题2:____ (hide) meaning.

Pub culture ____小题3:____(form) to improve sociability(社会交往) in a society that is known ___小题4:___ its coldness. Standing at the bar for service allows you to chat with others ___小题5:____ are waiting to be served. The bar counter is ____小题6:____ (possible) the only place in Britain ____小题7:____ a friendly talk with strangers is considered to be entirely proper and really quite normal behavior. However, ____小题8:____ you do not follow the local rules, the experience may fall flat(一无所获). For example, if you are in a big group, it is best for one or two people to go to buy the drinks. Nothing makes the regular customers and bar staff _____小题9:____(anger) more than a group of strangers blocking all passages(过道) to the bar while ____小题10:____ chat and hesitate(犹豫) about what to order.
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选择题

母亲是伟大的，母亲在怀孕期间，要为胎儿提供营养物质和氧气，排出胎儿所产生的二氧化碳等废物。母亲和胎儿之间进行物质交换的器官是

A．肝脏

B．肾脏

C．胎盘

D．输卵管
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