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The difference between '01/10/2006 4:39:11 PM' AND
'02/10/2006 4:39:11 PM' is smaller than 72 hours.
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'04/10/2006 4:39:11 PM' is equal to 72 hours.
The difference between '01/10/2006 4:39:11 PM' AND
'06/10/2006 4:39:11 PM' is bigger than 72 hours.