Answer: atoms
Explanation:
All matter is made up of smaller indivisible particles called atoms. These atoms are the smallest units of matter ACCORDING to the Dalton's Atomic theory.
Molecules are combined atoms, while cells and phospholipids are complex combination of atoms. 
Therefore, atoms is the answer 
 
        
             
        
        
        
Explanation:
Acceleration (a) = 600 m/s²
Mass (m) = 300 kg
Force (F) = ?
We know
F = m * a 
 = 300 * 600
 =180000 Newton 
The force acting on the object is 18000 Newton. 
 
        
                    
             
        
        
        
I think it is C. coefficients but I don't know what subscripts are
        
             
        
        
        
Molarity =  moles of solute / liters of solution
M = 0.5 / 0.05
M = 10.0 mol/L⁻¹
hope this helps!