Q. I separated from the Army in 1997 after nine years of active service and three years of National Guard service. I separated under the provisions of the Special Separation Benefit. My separation benefit was $38,000. I have recently received a job offer as a GS-12 employee. I’m 46 years old and wish to understand if buying back my military time would prove beneficial. Thank you.  A. If you become a federal employee and make a deposit for your nine years of active-duty service, you’ll be given credit for that time in determining your length of service and in your annuity calculation. As a rule, you’d…