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What is the purpose of the question in the Personal Info interview wherein it asks about military paygrade, and why is it important for tax purposes?  I ask because a midshipman at the US Merchant Marine Academy "shall be appointed by the Secretary of the Navy as a midshipman in the Navy Reserve (including the Merchant Marine Reserve, Navy Reserve)."  See 46 USC Sec. 51311(b).  Midshpman, however, are not cadets, warrant officers, or commissioned officers.  TT, therefore, does not have a grade that is appropriate for cadets.