Answer: D) protons.
The other option that would make the most sense would be electrons, however the mass of an electron is so small that is basically negligible, so it's not included in the atomic mass.
        
                    
             
        
        
        
Answer:

Explanation:
Given
The data in the table
Required
Follow the steps appended to the question;
Step 1: Calculate the Mean or Average
Mean = Summation of lengths divided by number of teams;



Step 2: Get The Range



Step 3: Divide Range by 2



Step 4: Determine the Precision

Substitute 2.70 for Average and 0.1 for Approximate Range

 
        
             
        
        
        
Electron -  In an atom, the central part which is composed of neutrons and protons including quarks is called the nucleus. Whereas the electron is the particle with negative elementary electric charge can be found inside the atom surrounding the nucleus.