I think it's wavelength
Hope I helped.
        
             
        
        
        
Answer:
Stable atom
Explanation:
A stable atom is one that has a balanced nuclear inter-particle force reaction as such the binding energy of a stable atom is sufficient to permanently keep the nucleus as one unit. Examples of a stable atom are the atoms of  monoisotopic elements such as fluorine, sodium, iodine, gold, aluminium, and cobalt.
In a stable atom the expected number of proton, neutron, and electron are present while in an unstable atom or radioactive atom, there are more than the expected number of neutrons or protons, such that the internal energy of the nucleus is excessive and more than the binding energy, which can lead to radioactive decay.
 
        
             
        
        
        
Meters for mass kilograms for volume cubic meters for density kilograms per cubic meter
        
             
        
        
        
Answer:
33.83W/m²
Explanation:
The intensity of the speake at the surface is 
I = P/A
I = 2.03W / 0.06m²
I = 33.83W/m²
 
        
             
        
        
        
Horizontal component = (10N) · sin (20°) =  3.42... N  (rounded)
Vertical component = (10N) · cos (20°) =  9.39... N   (rounded)