Answer is in the picture below.
Helium (symbol: He) is an element with atomic number 2 (two protons and two electrons) and mass number 4 (2 neutrons; n° = 4 - 2 = 2).
Electron configuration of helium atom: ₂He 1s².
Helium is a noble gas.
Noble gases are in group 18: helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn). They have very low chemical reactivity.