Answer:
Blue and Green marbles
Step-by-step explanation:
We have been given that:
Number of Marbles:
Blue(Protons) = 3
Green(Neutrons) = 4
Red (Electrons) = 3
The marble that should be placed in the nucleus of a lithium atom = ?
Solution:
The nucleus of an atom is made up of protons and neutrons.
Protons are the positively charged particles in an atom.
Neutrons do not carry any charges.
So;
The marble in the nucleus are the Blue and Green marbles.