Final answer:
The flying disk stayed in the air for approximately 10.69 seconds, calculated by dividing the distance thrown by the average speed.
Step-by-step explanation:
To determine how long the flying disk remained in the air, we can use the formula time = distance / speed. In this case, the athlete threw the disk 139 meters and the disk traveled at an average speed of 13.0 m/s.
Time = Distance / Speed
Time = 139 meters / 13.0 m/s
Time = 10.69 seconds
Therefore, the disk remained in the air for approximately 10.69 seconds.