Answer:

Explanation:
from the ideal gas law we have
PV = mRT 


HERE  R is gas constant for dry air  =  287  J K^{-1} kg^{-1}


We know by ideal gas law



 for m_2 



 
WE KNOW 
PV = mRT
V, R and T are constant therefore we have
P is directly proportional to mass




 
        
             
        
        
        
Answer:
Social media has helped many businesses grow and promote itself, and has helped people find a better way to connect and communicate with one another. On the other hand, it's also provided many people with problems involving mental health, emotional insecurities, and waste of time
Explanation:
what they said is correct
 
        
             
        
        
        
Answer:
ni = 2.04e19
Explanation:
we know that in semiconductor like intrinsic, when electron leave the band, it leave a hole in valence band so we have 
n = p = ni
from intrinsic carrier concentration



1.7 = ni * 1.6*10^{-19} * (.35 + .17)
ni = 2.014 *10^{19} m^{-3}
ni = 2.04e19
 
        
             
        
        
        
Because water is more dense than the object but rubbing alcohol is less dense than the object