Answer: For the center plate to remain stationed in one position without rotating, the bottom plate has to move to the left at a speed of 2m/s, so as to cancel the force acting on it from the top. 
The center plate will not move when the bottom plate is moving left in a speed of 2m/s to counter the speed of the top plate, because a body will continue to be at rest if all the forces acting towards the body are equal. The center plate will be at rest because we have directed equal force from the top and bottom of the plate.
 
        
             
        
        
        
The person that is correct as regards statement made about stoichiometric ratio is; <em><u>Tech B</u></em>
In air-fuel mixture, when there is a mix air and fuel in the ideal amounts to make an engine to run efficiently,the ideal ratio of air to fuel is known Stoichiometric ratio. 
This stoichiometric ratio is the comparison between the weight of the air relative to the weight of the fuel that it has been mixed with. 
Now, weight is in lb and as such, tech B is correct because his ratio is 14.7lb to 1 lb. 
Read more at; brainly.com/question/16971089
 
        
             
        
        
        
Following are the two sources of data:
- Internal Source. When data are collected from reports and records of the organisation itself, it is known as the internal source. ...
- External Source. When data are collected from outside the organisation, it is known as the external source.
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