Final answer:
In aviation, ground time is added to the total duration of a cross-country flight for landing, taxi, and takeoff operations.
Step-by-step explanation:
In aviation, the time added to the total duration of a cross-country flight for landing, taxi, and takeoff operations is known as the ground time. This ground time is necessary to account for the various activities involved in these operations, such as runway clearance, taxiing to and from the gate, and preparing for takeoff. The exact duration of ground time may vary depending on the airport and specific circumstances, but a common rule of thumb is to add about 30 minutes to an hour for these activities.