Has varied greatly over time
        
                    
             
        
        
        
The substance is colder than it was because when particles move very quickly its either how or boiling so if its slow its cold and if it freezed the particles are well frozen
        
             
        
        
        
<span>4 molecules of oxygen. Haemoglobin is a protein found in the red blood cells, which carries oxygen to the cells to perform cellular respiration. Each red blood cell carries around 250 million haemoglobin. So the entire capacity of an RBC is around 1 billion oxygen molecules.</span>
        
             
        
        
        
There are convergent,divergent and transform boundaries and convergent sits in the subduction zone and the divergent is two plates moving apart from each other and transform us where plates slide passed each other? Hope it helps I tried.