  
 For free space wavelength (in cm) =   
 
    10.  
 
     TE10 can propagate   
 
     TM11 cannot propagate   
 
     TM21 cannot propagate   
 
 For free space wavelength (in cm) =   
 
    5.  
 
     TE10 can propagate   
 
     TM11 can propagate   
 
     TM21 can propagate 
