题干

已知数据x1,x2,x3,…,xn是武汉市n(n≥3,n∈N*)个普通职工的2014年的年收入,设这n个数据的中位数为x,平均数为y,方差为z,如果再加上比尔.盖茨的2014年的年收入xn+1(约80亿美元),则这n+1个数据中,下列说法正确的是(  )

A:年收入平均数大大增大,中位数一定变大,方差可能不变

B:年收入平均数大大增大,中位数可能不变,方差变大

C:年收入平均数大大增大,中位数可能不变,方差也不变

D:年收入平均数可能不变,中位数可能不变,方差可能不变

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B

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    Open work spaces definitely have their benefits,but they come with the drawback of offering employees little to no control over visual distractions(干扰).With so many people around and so much going on,some of us can easily get disturbed by this information overload and lose focus in what's really important.That's where the Focus Cap comes into play.

    “As we are still cavemen or mammals kept in an unnatural environment,I believe that only by reclaiming(收回)the normal,stress-free human state through simple tools and techniques can we finally release our actual creative potential and create our meaningful work for a brighter future,”says German designer Hannes Greblin,inventor of the Focus Cap.

    After looking at other products designed at minimizing visual distractions,Greblin decided that most of them were either too expensive or too uncomfortable to become mainstream,so he decided to go with something much simpler —a simple cap with a retractable visor(可伸缩的帽沿).

    Greblin's Focus Cap is really straightforward.You just wear it like a regular cap'with the sides of the visor retracted,and just collapse the sides whenever you need to focus on what's ahead of you.Whether you're trying to focus on a task in an open work office.Trying to study at university,or practicing yoga in a park and trying to ignore stares from strangers,the Focus Cap can help.

    To be honest,this whole project sounds like a joke,but the Focus Cap does have its own website where people interested in this unusual accessory can actually sign up for updates on when it will go on sale.Greblin claims it will cost 30 euros($37)plus shipping.