It's these two numbers, 20 and 13, that are used to make up the Tzolk'in calendar, the first calendar used by the Mayans. 1  1. 2  2. 3  3. 4  4. â¦. 5  5. 6.  NEXT.
Making the world better, one answer at a time. the nucleus is made up ofneutrons and protons. on the outside of the nucleus is the electrons. the nucleus is made up ofneutrons and protons. <br/>on the outside of the nucleus is the electrons.
Atoms are made of extremely tiny particles called protons, neutrons, and electrons. Protons and neutrons are in the center of the atom, making up the nucleus. Electrons surround the nucleus. Protons have a positive charge. Electrons have a negative charge.