What is proper salutation for FBI supervisory senior resident agent?

can you help me i need to know what is noun proper and common plaes can you help me

Added: Generally, a Special Agent-in-Charge is called a "SAC." However, Special Agents within the FBI feel calling someone a "sac" may be a derogatory comment to a Supervisory Special Agent. Instead they spell it out like: "S-A-C," and include the person's last name, S-A-C Lewis when referring to him or her. When speaking to them proper address would be: "Mr. Lewis."

If I may correct your understanding also, the FBI is commanded by a Director and a Field Office is commanded by an Assistant Director-in-Charge, if a large field office such as Los Angeles. In large field offices Special Agents-in-Charge, command divisions, such as Counterterrorism Division.