How do i do this because i don't get what i'm supposed to do on the paper

Your supposed to find an element and other info from the periodic table and fit in in each row. For example the first row is B and the Atomic number would be 5 and protons would be 5 because the atomic number is the same as the atomic mass. Also, you would need to look up a periodic table for this. and google. Boron's neutrons would be 6 and electrons would be 5. The mass number would be 10.811.

The answer is c hope this