An atomic mass unit (symbolized AMU or amu) is defined as precisely 1/12 the mass of an atom of carbon-12. The carbon-12 (C-12) atom has six protons and six neutrons in its nucleus. In imprecise terms, one AMU is the average of the proton rest mass and the neutron rest mass.
        
             
        
        
        
Electrical energy !! i hope this helped :))
        
             
        
        
        
Answer:
Exposure of silver chloride to sunlight for a long duration turns grey due to photolytic decomposition i.e decomposition in the presence of sunlight. 
Explanation:
When silver chloride, AgCl is exposed to sunlight for a long time, it will undergo decomposition as the sunlight provides sufficient energy needed to decomposed the salt, AgCl to metallic silver and chlorine gas. This can be seen in the equation below:
2AgCl —> 2Ag + Cl2
 
        
             
        
        
        
Answer: 4 molL-1
Explanation:
Detailed solution is shown in the image attached. The number of moles of NaCl is first obtained. Since the molarity must be in units of molL-1, the volume is divided by 1000 and the formula stated in the solution is applied and the answer is given to one significant figure.