The notation for the nuclide 13755cs gives information about
(1) mass number, only
(2) atomic number. only(3) both mass number and atomic number(4) neither mass number nor atomic number

Answer is (3) both mass number and atomic number.

The notation is ₅₅¹³⁷Cs. The Cs represents the chemical symbol of Caesium element. The subscript number at the left hand side of the symbol indicates the atomic number. Hence, atomic number of Cs is 55. The superscript number at the left hand side of the symbol shows the mass number. Hence, the mass number of the Cs is 137.

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d.) gravity pulled particles of dust and gas together to form planets.