<Li> follows the border between Nevada (west) and Arizona (east) </Li> <Li> follows the border between California (west) and Arizona (east), mostly defined by the Colorado River, to the border between the U.S. and Mexico . </Li> <P> The Energy Policy Act of 2005 extended daylight saving time (DST) for an additional month beginning in 2007 . The start of DST now occurs on the second Sunday in March and ends on the first Sunday in November . </P> <P> Clocks will be set ahead one hour at 2 a.m. on the following start dates and set back one hour at 2 a.m. on these ending dates: </P>

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