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This is Scientific Americans 60-Second Science. Im Karen Hopkin. This will just take a minute. Those of you following the World Cup know that at this stage there can be no more draws. Ties are broken during overtime play, or in a penalty kick shootou
World Bank President: Elimination of Poverty Possible World Bank President Jim Yong Kim says the problems of poverty, hunger and inequality are massive, urgent and a matter of survival for millions. We know that despite the dramatic successes of the
Green Card Lottery Faces Elimination Under US Immigration Reform Two years ago Rafiq-ul-Islam won a U.S. permanent resident visa through the Green Card Lottery and came to the United States from Bangladesh -- with little more than the clothing he own
By Lisa Schlein Geneva 02 May 2006 Environmentalists are calling for the elimination of the toxic chemical, DDT, which is still used in large parts of Africa to combat malaria. The continued use of DD
Parallax is a phenomenon by which we can judge the distance to things just by looking at them. Astronomers use parallax to calculate the distance to stars. Do you need a gigantic computer-based observatory to use it? Not at all. Your finger will do n
Parallax 视差就是从有一定距离的两个点上观察同一个目标所产生的方向差异。从目标看两个点之间的夹角,叫做这两个点的视差,两点之间的距离称作基线。只要知道视差角度和基线长度,就