Answer:
Explanation:
From the question we are told that mass
Thin layer radius 
Generally the expression for ths solution is given as
Xcm =(m*0 =m(-2R))/2m =-mR/(2m)=-R/2
the center of mass will not move at initial state
Considering the center of mass of both bodies


Therefore the enclosing layer moves
Answer:

Explanation:
Given:
- mass of rocket,

- time of observation,

- mass lost by the rocket by expulsion of air,

- velocity of air,

<u>Now the momentum of air will be equal to the momentum of rocket in the opposite direction: </u>(Using the theory of elastic collision)



There is no theoretical OR observational evidence for that statement.