We donÃ¢Â€Â™t know what it will cost to build the next nuclear power plant in the US.
Congress helped bolster the corn ethanol business in Iowa by mandating the Renewable Fuel Standard in 2005. But scientists are concerned about the unexpected consequences of putting more of Iowa's land into corn production Ã¢Â€Â” consequences that may make corn ethanol a bigger source of climate-warming gases than regular gasoline.
The flow of water in Montana's rivers is lifeblood for its economy, both through tourism and agriculture. Montana's recreational fishing and agricultural industries depend on cool waters flowing from melting snow high in the mountains throughout the summer. But across Montana, rising temperatures are causing a series of changes.