What is a t2k file and how do I open a t2k file?

This file extension is primary used by Teach 2000 which is a flashcard/memory training program used for the teaching of foreign languages.  It provides a list of questions (free form or multiple choice) in an XML format.  Specifically these T2K files are used for saving memorization questions which can later be executed as a test.  One can also use these files to subsequently create T2KT files which can be distributed as digital tests to students. This file extension is also used by Mirror Suite by Canfield Scientific, highly sophisticated graphic software used on patients by hospitals.  One common use of this software is the ability to show prospective patients a simulation of their potential appearance often used by aesthetic surgeons.  This is frequently used in breast and nose simulations prior to operations being conducted.  This software is primarily used in the US but slowly being introduced in hospitals worldwide.