plateaus (which dominate the landscape)
huge mountains.
long rivers.
large lakes.
massive deserts.
deep valleys.
dense rainforests.
expansive grasslands.
By sending spies to the USSR to copy their plans for sputnik
Answer:
The speed of the airplane is approximately 770 km/h (214 m/s).
Explanation:
Speed = 
Distance = 3080 km
Time = 4 hours
speed = 
= 770
speed = 770 km/h
The speed of the airplane is 770 km/h.
OR
Distance = 3080 km
But,
1 000 m = 1 km
3080 km = 3080000 m
distance = 3080000 m
Time = 4 hours
60 seconds = 1 minute
60 minutes = 1 hour
Thus, 4 hours = 60 x 60 x 4
= 14400 seconds
Therefore,
speed = 
= 213.8889
speed ≅ 214 m/s
The speed of the airplane is approximately 214 m/s.