The rank is Specialist 5th Class, which is grade equivilent to a (3 chevrons) Sergeant.
The ribbon is the Defense Service ribbon that is issued to virtually all who have served. The badge on the pocket is an expert marksmanship badge and the two bars under the badge should indicate the weapons the soldier qualified with.
The American Eagle with the five sided edge is the unit patch for soldiers assigned to the Pentagon.
The left shoulder is where the current unit patch is displayed. The right shoulder would display one of the unit patches where the soldier served in a combat zone. Since this uniform has no patch on the right shoulder, the original owner did not serve in combat (at least at the time this uniform was worn)
Since there are no hash marks on the left sleeve, the soldier who owned this Class A uniform blouse (not jacket) served less than 3 years at the time this uniform was worn.
The Enlisted Branch of Service device on the left collar, in this case is "unassigned to any branch" that is often worn by soldiers assigned to duties in the Pentagon.
