Complete the isotope symbol with mass numbers of 35

Explanation:

It is known that isotopes are the species which have same atomic number but different mass number. Whereas a specie which have different atomic number but same mass number are known as isobars.

For example, an element with mass number 35 is chlorine. And, atomic number of a chlorine atom is 17.

This means in a atom there are 17 protons and the number of neutrons will be calculated as follows.

                   Mass number = no. of protons + no. of neutrons

                          35 = 17 + no. of neutrons

                  No. of neutrons = 35 - 17

                                             = 18

Hence, we can conclude that the isotope symbol with mass numbers of 35 is .

idk i’m struggling too