Question:
column1 contains the days of 2011. I want to get the new column2 which converts the days in column1 into Month/week#,.For example, for Feb of 2011, the week1 is from Feb. 1  to Feb. 6 (sunday), week2 is from Feb. 7 (monday) to Feb. 13 (sunday) and so on...

Column1
2/01/2011
2/21/2011
3/01/2011
4/05/2011
.
.
so the column2 I want is
Column2
Feb/Week1
Feb/Week4
Mar/Week1
April/Week2

How to get the Week number? is there anybody can help me? or give me some hints? Thanks a lot!