Americans invest a great deal of effort in monitoring and cultivating their physical, financial, and human capital. The environment and the ecosystem, on the other hand, are just beginning to receive attention. Over the last three decades, there has been a growing recognition that pollution poses a serious threat to human population and global ecosystems. One realization is that the ozone layer is weakening. In fact, estimates show that the ozone hole is as big …
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showed last 75 words of 3042 total
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