Related: Environment

1. More environment
   1. Got water? Keeping it flowing could get expensive
   2. World population could hit 11 billion by 2100
   3. Endangered California frogs let loose in wild
   4. 2012 natural disaster costs one for record books
   5. Largest solar sail ever to launch in 2014
2. More U.S. news
   1. Former hitman says Whitey Bulger 'broke my heart'
   2. Naval Academy trio to face sex assault charges
   3. One Fund Boston receives over 200 applications
   4. Court: States can't force voters to prove citizenship
   5. Feds digging in Michigan field for Hoffa's remains
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