Final answer:
IFR flight is permitted in the Northern Control Area from FL 300 and above.
Step-by-step explanation:
IFR flight is permitted in the Northern Control Area from FL 300 and above. This means that Instrument Flight Rules (IFR) flights are allowed at altitudes of 30,000 feet and higher in the Northern Control Area. IFR flights require pilots to rely on instruments for navigation and control rather than visual references.