1. Two United States cities have seen significant increases in costs, with Los Angeles rising 19 places to enter the top 10.
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3. Last month scientists at Illinois University made a breakthrough that could herald a second green revolution for world agriculture – they improved the efficiency of photosynthesis, the process by which plants turn sunlight into the biomass that is the source of all our food.
4. Piggyback riders are designed especially for small children and toddlers, to lessen the parents’ struggles.