If 1st January, 2007 is Monday, then what was the day on 1st January, 1995?

From 1 January 1995 to 1 January 2007 there are 12 years, including leap years 1996, 2000, and 2004. The shift is 12 + 3 = 15 days, i.e. 1 day modulo 7. Since 1 January 2007 was Monday, 1 January 1995 was Sunday.