Since the number on top is the mass number (number of neutrons and protons) while the number at the bottom is the atomic number ( number of protons)
A) 13 protons, 14 neutrons (27-13)
For the number of electrons it has to be equal to the number of protons if the atom is uncharged.
Therefore you have 13 electrons.
B) 17 protons, 18 neutrons (35-17)
18 electrons
C) What is the atomic number of Sulphur - need slightly more info
