Final answer:
To model a carbon atom, you can use red marbles to represent protons and neutrons, blue marbles for electrons, and yellow marbles to show covalent bonding.
Step-by-step explanation:
To model a carbon atom using red, blue, and yellow marbles, you can represent the protons and neutrons in the nucleus with red marbles.
The electrons can be represented with blue marbles, with each blue marble placed in its own orbit around the nucleus.
The yellow marbles can be used to represent the bonding electrons involved in covalent bonding, with each yellow marble connecting two blue marbles to show the sharing of electrons.