题干

菠菜叶进行“叶绿体中色素提取和分离”的实验,滤液经层析后,色素带在滤纸条上的分布顺序是(    )

A:

B:

C:

D:

上一题 下一题 0.0难度 选择题 更新时间:2019-05-08 02:04:02

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A

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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.

同类题2

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(《后汉书·赵咨传》有删节)