Thr answer is c sorry if am wrong
        
             
        
        
        
So they can handle the tough terrain, like rocks and dirt and gravel and harsh grounds.
They way they have an advantage of actually being able to move places
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Answer:
D 
Explanation:
it has to be D because its talking about "how does a volcanic ash affect water systems"
 
        
             
        
        
        
Answer:
30meter per second
Explanation:
Given that
Distance = 3000 meters
Time = 100seconds
Speed = distance /time
Substituting the values
Speed = 3000/100
Speed = 30meter per second
The average speed needed to cover the travelling will be 30meter per second.