If it was Wednesday on 1 January 2007, then what was the day of the week on 1 January 2011?
The number of days in between 1 January 2011 and 1 January 2007 is 1461.
1461%7 = 5. So, if 1 January 2007 is Wednesday then 1 January 2011 is Monday(5 days after Wednesday).