Most I/O intensive query in last 6 hours

Hi All,

I am on SQL 2008 R2.

I want to find out which has been the most I/O intensive query on my data server in last 6 hours (or say 3 hours). How can I do that (without using Third party tools) ?

Also, if I want to check, amongest the currently running queries, which is the most I/O intensive (and/or which has done lot of physical I/O, logical I/O), how can I do that?

Thanks in advance