Why must the fire alarm be blue?

The blueprint must be reported to the fire department, because it is printed, not printed, and the blueprint cannot be modified after being smoked, so the blueprint is true.

As for the problem of pests, one way to save documents at present is to save them in an inert gas environment, and the other way is to take photos of the original pictures through micro-photography. Of course, there may be some left in filing cabinets like this.