题干

在一个不透明的纸箱中放入m个除颜色外其他都完全相同的球,这些球中有4个红球,每次将球摇匀后任意摸出一个球,记下颜色再放回纸箱中,通过大量的重复摸球实验后发现摸到红球的频率稳定在
1
5
,因此可以估算出m的值大约是(  )

A:8

B:12

C:16

D:20

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D

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    Alibaba opened China's version of Amazon's cashier-less store, “Tao Cafe” at its second annual Taobao Maker Festival taking place from 8—12 July, and then showed it to the public. By scanning a QR code(二维码)on Taobao app at the entrance of the store« consumers are tracked with cameras for facial recognition. After going through the checkout doors, customers will automatically make a purchase through their smartphones without needing to head to a register and be able to leave the store with what they buy in hand.

    The company, putting its efforts in Artificial Intelligence and data technologies, caused some ripples(波动)among offline retailers (零售商). But if you think the e-commerce giant plans to get a slice of the physical-store pie, then you might get it wrong: “It's not about Alibaba wanting to open more cafes, we are not in the restaurant business.” it's about digitalizing the footprints of the visitors to an offline store, '' said Chris Tung, chief marketing officer of Alibaba Group.

    He said, for example, in the online world, Alibaba can always personalize every web page based on users interest and preference thanks to big data, “When you open our app, every moment is different.” But on the other hand, “offline is becoming not so exciting anymore”, because many physical stores are always found to be very similar with no variation.

    Tung said offline retailers could improve by adopting online data competence to link the identity of the customers» and optimize(优化)their in-store shopping experience. So in this sense, after physical stores have an understanding of what their customers need online, then they can allocate the products in the physical offline store accordingly. He further explained the pop-up Tao Cafe is one of the ways to present this “new retail” idea and opens up people's thinking and calls for more partnership.