Answer
It should be A and C 
Explanation:
because oxygen is number 8 in the periodic table of elements and has a atomic weight of 15.999 you use those numbers to figure out what is true between those.
The 8 for oxygen goes for the number of electrons and proton and to find neutrons u round the 15.999 up which now make it 16 and subtract it by the 8 now you have 8 protons, 8 neutrons, and 8 electrons 
 
        
             
        
        
        
If it is a true or false question then it is true
        
             
        
        
        
The answer should be speed hope this helps
        
                    
             
        
        
        
Answer:
Rest and motion are the relative terms because they depend on the observer's frame of reference. So if two different observers are not at rest with respect to each other, then they too get different results when they observe the motion or rest of a body.