A floor furnace must be placed so that no object can be nearer than how many inches?

The correct answer is 12 inches because building codes and safety regulations typically dictate that appliances, such as floor furnaces, must have a specific clearance from any combustible materials to ensure safe operation. This distance is crucial to prevent the risk of fire hazards and to allow for adequate airflow around the furnace.

By maintaining a spacing of 12 inches, you help ensure that there is enough room for heat dissipation, and it reduces the likelihood of any furnishings or other nearby objects igniting due to the heat emitted by the furnace. Compliance with this requirement is critical for maintaining safety in residential or commercial properties where such heating systems are installed.

While other clearances could potentially be relevant in different contexts or with different appliances, the specified requirement of 12 inches is established to create a safe operating environment for floor furnaces based on industry standards.