题干

如图,在边长为1个单位长度的小正方形组成的网格中,△ABC与△DEF关于点O成中心对称,△ABC与△DEF的顶点均在格点上,请按要求完成下列各题

(1)则OB等于多少;

(2)将△ABC先向右平移4个单位长度,再向下平移2个单位长度,得到△A1B1C1,请画出△A1B1C1

(3)在网格中画出格点M,使A1M平分∠B1A1C1

 

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答案(点此获取答案解析)

解:(1)连结BF、AD、CE,它们相交于点O,如图,
OB=22+22=22

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阅读理解

    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.