Answer:
a natural process is water cycle.
Explanation:
during this process,water evaporates from different water bodies ,when the warm water rises,the cold and heavier water comes down to take its place.On the other hand,the warm water on rising,changes to water vapour.
This water vapour helps in the formation of clouds .
When the cloud becomes heavy and is not able to hold the water vapour, it falls down as rain or snow depending upon the climate and atmospheric temperature. 
This process continues over and over again 
 
        
             
        
        
        
An electron has a relative mass of 0, whilst an alpha particle has a relative mass of 4
An electron has a relative mass of 0, whilst a proton has a relative mass of 1
A neutron has a relative mass of 1, whilst an alpha particle has a relative mass of 4
A neutron has a relative mass of 1, and a proton also has a relative mass of 1
        
             
        
        
        
Answer:
c
Explanation:
because forces act on an object and make it change direction based upon strength hope this helps.