Sand particles are known to move everywhere and are a part of the geosphere 
        
             
        
        
        
Another name for unicellular organisms that dominated Earth up to the Precambrian time is prokaryotes. The correct answer is D. 
        
                    
             
        
        
        
Interneurons are those neurons that transduces the vague information received from the afferent neurons and sends a response to the efferent neurons. 
Neurons are the basic unit of the nervous system. Hence, these nerve cells are the cells that transmits electrical impulses that causes a person to respond, move and irritable (respond to stimuli). 
        
             
        
        
        
Answer:
B
Explanation:
If it is denser it will more likely sink because of convection currents forcing it down.