Transmission of light is the moving of electromagnetic waves (whether visible light, radio waves, ultraviolet, etc.) through a material. This transmission can be reduced, or stopped, when light is reflected off the surface or absorbed by the molecules in the material.
An FBI agent at GS-12 step 5 would earn an annual salary of  $68,993. More experienced agents with longer tenure will have a higher grade and step rating. An agent at GS-14 step 1 would earn $85,544, while an agent on GS-14 step 4 would have an annual salary of $94,097.
According to the CIA website, CIA Agent income ranges from $52,976 to $81,204 per year. The U.S. Bureau of Labor Statistics reports that federal Detectives and Crime Scene Investigators earn an annual average income of $68,820.