What is the number of protons, electrons, and neutrons in boron-$11$?

Which statements about the isotopes of chlorine, ${}_{17}{}^{35}\mathrm{Cl}$ and ${}_{17}{}^{37}\mathrm{Cl}$, are correct?

I. They have the same chemical properties.

II. They have the same atomic number.

III. They have the same physical properties.

A sample of element $\mathrm{X}$ contains $69\%$ of ${}^{63}\mathrm{X}$ and $31\%$ of ${}^{65}\mathrm{X}$. What is the relative atomic mass of $\mathrm{X}$ in this sample?

What is the relative atomic mass of an element with the mass spectrum shown in figure?