Conduction and convection both require some material substance 
to move heat from one place to another, and there's none of that 
between the sun and Earth.  
The only way for thermal energy to move from place to place with 
nothing in between is by the process of radiation, and that's how 
it gets here from the sun. 
        
             
        
        
        
Answer:
Explanation:
Before Thomson's discovery, atoms were believed according to the "Dalton's atomic theory" to be the smallest indivisible particle of any matter. This makes atoms the smallest unit of a matter. 
Thomson in 1897, used the discharge tube to discover cathode rays which are today called electrons. 
The discovery of electrons provided more light into the structure and nature of atoms. Atoms were now being seen in a different light as particles that are made up of other smaller sized particles. 
Thomson through his experiment was able determine perfectly well the nature of the rays he saw emanating from the cathode. One of his findings shows that the rays are negatively charged and are repelled by negative charges. 
The discovery of electrons further led to more works on the atom and other particles were discovered. Atoms were no longer seen as indivisible or the smallest particles of matter. 
 
        
             
        
        
        
Deltas are complex depositional landforms that develop at the mouths of rivers. They are composed of sediment that is deposited as a river enters a standing body of water and loses forward momentum. Famous deltas include the Mississippi delta in Louisiana and the Nile delta in Egypt.