NPR's A Martinez speaks with associate professor Chloe East of the University of Colorado Denver about the impact of undocumented immigrants on the U.S. housing market.
Two years ago, scientists surveyed the floor of Lake Michigan looking for shipwrecks. They found something mysterious and unexpected — a cluster of sinkholes on the lakebed.
Vision impairment is a common problem in large parts of Asia, Africa and Latin America. It has a serious effect on economies. One solution: providing eye glasses. But it turns out that can be tricky.