Explanation :
Isotope : It is defined as the element that have the same number of protons but have the different number of neutrons of each of the atom.
Atomic number is defined as the number of protons or number of electrons.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and number of neutrons.
Number of neutrons = Mass number - Number of protons
For the given options:
(a)
Atomic number = 5
Number of proton = 5
Number of electron = 5
Atomic mass = 10
Number of neutrons = Atomic number - Number of protons
Number of neutrons = 10 - 5 = 5
(b)
Atomic number = 80
Number of proton = 80
Number of electron = 80
Atomic mass = 199
Number of neutrons = Atomic number - Number of protons
Number of neutrons = 199 - 80 = 119
(c)
Atomic number = 29
Number of proton = 29
Number of electron = 29
Atomic mass = 63
Number of neutrons = Atomic number - Number of protons
Number of neutrons = 63 - 29 = 34
(d)
Atomic number = 6
Number of proton = 6
Number of electron = 6
Atomic mass = 13
Number of neutrons = Atomic number - Number of protons
Number of neutrons = 13 - 6 = 7
(e)
Atomic number = 34
Number of proton = 34
Number of electron = 34
Atomic mass = 77
Number of neutrons = Atomic number - Number of protons
Number of neutrons = 77 - 34 = 43