Answer:
freqiency=velocity/wavelength
ief=20/2000=0.01hz
Answer:
The value is 
Explanation:
From the question we are told that
The landing speed is 
The distance traveled is 
The velocity it is reduced to is 
Generally the average acceleration is mathematically represented as

=> 
=> 
I think there might be less pollution
Answer: Answer below hope it helps
Explanation: How does a rubber rod become negatively charged through friction? It touches a negatively charged object, and protons move off of the rod. ... It is rubbed with another object, and electrons move onto the rod. It is rubbed with another object, and protons move off of the rod.