Final answer:
The aggregate area of mezzanines typically must not exceed a certain percent of the floor area of the room, often around 33%, but this can vary by building codes. For floor area with an uncertainty of 3 percent on a 12.0 m² measurement, the uncertainty is rounded to 0.4 m².
Step-by-step explanation:
The question pertains to the maximum allowable size for a mezzanine within a given space according to building codes or regulations. While the specific value is not provided in the question, building codes typically specify that the aggregate area of mezzanines shall not exceed a certain percent of the floor area of the room or space where they are located. This percentage varies by jurisdiction and code, but common limits might be around one-third or 33%. To address the mention of uncertainty, when a floor area is measured to be 12.0 m² with an uncertainty of 3 percent, this translates to an uncertainty of 0.36 m². As per mathematical convention and significant figures, this value can be rounded to 0.4 m² because the floor area provided is to one decimal place.