题干

上周学校购买了一批水龙头,据商家说其材料铜质的,实验室的老师组织九年级的一些同学通过实验来验证商家的说法。他们把一个水龙头用轻质细线捆好后挂在弹簧测力计上,在空气中测得它的重力为1.6N,再把这个水龙头浸没在水中,如图所示,这时弹簧测力计的读数为1.4N(ρ=8.9×103kg/m3,g=10N/kg)。求:

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Rob

     I don't think there is a solution to the environmental problems. The world population is now too large. We are going to run out of natural resources.

    Global warming shows us the effect that human beings have on the planet. Soon, millions of people will start leaving some parts of the world, because it will be impossible for them to live there any more, which in turn will create a whole new set of problems.

Louise

   The environmental situation is very serious, but I believe human beings can solve the problems.

   For example, we have already had clean ways of making electricity, like nuclear (原子能的) power and wind power.

   Besides, I think in the end, most people will want to help solve the problems. People just need to be made more aware of the problems and shown ways how they can help.

Michael

   We can now see that there has been a huge price to pay for the economic (经济的) development, because we have used a lot of natural resources and polluted the Earth.

   Of course, we can do many things to protect the Earth. For example, we can recycle (回收利用) or drive cars that pollute a bit less, or even use fewer plastic bags. However, I really don't know if these small things are going to be enough to solve the problems.

Rob

     I don't think there is a solution to the environmental problems. The world population is now too large. We are going to run out of natural resources.

    Global warming shows us the effect that human beings have on the planet. Soon, millions of people will start leaving some parts of the world, because it will be impossible for them to live there any more, which in turn will create a whole new set of problems.