what would be the answer for this puzzle- FSSMTW_ clue is,this is the puzzle of all your periodic life in your day to day life

Question

 This is an IQ question.... actually its a puzzle.... u have to find out the last letter after W' 

Answer 1

Many, many such IQ questions want you to relate words (like in an acronym) to the letters presented.  These look suspiciously like days of the week (that is, periods of "day to day").  Also note:  sometimes "R" is used to avoid confusion with "T" already used (but they gave you "S" and "S," so use "T" to complete the weekly period).