It is 29
27.5
29
18, 20, 22, 24, 26, 28
29
The answer is 29.
29
The mass number of an iron is determined by the total number of protons and neutrons. Iron has an atomic number of 26, meaning it has 26 protons. If the iron atom has 29 neutrons, the mass number would be 26 (protons) + 29 (neutrons) = 55.
The numbers between 26 and 30 are 27,28 and 29.
29, as it is the middle number when they are arranged in numerical order.
29
29 is.