Which I concur with.
A preposition is nothing to end a sentence with.
Maybe...
https://www.google.com/search?q=A+preposition+is+nothing+to+end+a+sentence+with.&sourceid=ie7&rls=com.microsoft:en-US:IE-Address&ie=&oe=&rlz=1I7ADRA_enUS475&gws_rd=ssl