What is the maximum number of electrons in the M-Shell ?

The number of maximum electrons in N shell is

What is the maximum number of electrons that can occupy the first shell of an atom ?

What is the number of moles of ‘He’ in 104 g of helium gas?

What is the mass number of an element, the atom of which contains two protons, two neutrons and two electrons?

The number of electrons and neutrons in an element is 18 and 20 respectively. Its mass number is