FILE -- In a Jan. 12, 2011 file photo, a third generation Toyota Prius is shown at the North American International Auto Show in Detroit. U.S. car buyers bought a record number of hybrid and electric ... more 
FILE -- In a Jan. 12, 2011 file photo, a third generation Toyota Prius is shown at the North American International Auto Show in Detroit. U.S. car buyers bought a record number of hybrid and electric cars in March 2012, as new models went on sale and gas prices neared $4 per gallon. (AP Photo/Paul Sancya, File) less 
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Associated Press | Photo By Paul Sancya, File
Fri, Apr 13, 2012 4:53 PM EDT