题干

下列关于有机物的说法正确的是(   )

A:企鹅分子(如下图)中所有的碳原子可能共处同一平面

B:乙酸与2-羟基乙醛互为同分异构体

C:甲醇与甘油互为同系物

D:工业制备聚丙烯方程式为: nCH2=CH-CH3

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B

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    Technology is everywhere. We see it any place we go and, in fact, almost all of us carry some piece of technology with us every time we leave the house. What I always forget, though, is just how useful and powerful technology can be when we want to help others.

    There is not a single room in my house that does not have some electronic devices(设备)lying around in it. Whenever I am at home, I am almost always using at least one electronic device. If you walked into my living room on any given day, you would find that, first, I have the television on. At the same time, I usually have my laptop resting on my knee, or I will be using my mobile phone. Even when I'm not at home I am always using my phone, and at work or in cafes, I sit down and connect to the local wireless network on my laptop.

    I must say that I waste a lot of time on the computer and the time I spend on it could be much better spent if I were to take up a little online volunteering.

    The technology we carry about everywhere can have a great power to do good for the world and to help others and recently I discovered just how much online volunteering there is to do in the world. From using your language skills to do translations, to developing and managing projects and helping with IT work, there is so much that so many people can do to help people in their own countries and across the world. The United Nations, in fact, has a huge page with "Volunteers Recruited" on its website.

    This work can support the poor and help charities who cannot pay for staff. Many organizations only require you to work an hour a week-some even less. And the support provided by online volunteers can really help make a difference to those in need.