Final answer:
The average speed of the airplane is 720 kilometers per hour.
Step-by-step explanation:
To calculate the average speed of an airplane, we can use the formula:
Average speed = Distance / Time
In this case, the distance traveled by the airplane is 1980 km and the time taken is 2.75 hours.
Plugging these values into the formula, we get:
Average speed = 1980 km / 2.75 hours = 720 km/h
Therefore, the average speed of the airplane is 720 kilometers per hour.