Answer:
the mass of the body is 0.02 kg.
Explanation:
Given;
relative density of the oil, 
 = 0.875
mass of the object in oil, 
 = 0.013 kg
mass of the object in water, 
 = 0.012 kg
let the mass of the object in air = 
weight of the oil, 
weight of the water, 
The relative density of the oil is given as;

Therefore, the mass of the body is 0.02 kg.
 
        
             
        
        
        
I am pretty sure the answer is C.
 
        
             
        
        
        
The movements of the tectonic plates
        
             
        
        
        
It's a physical change. the water is changing it's physical state
        
                    
             
        
        
        
The momentum of the rolling ball will have less momentum than before the collision and the stationary ball will have more momentum after the collusion.