Answer:
the symbol that is missing might be 2.
Explanation:
I am not 100% on this, so correct me if I am wrong.
The correct answer is C. Atoms are incredibly small and can bearly be seen with the most powerful electron microscopes. The nucleas of an atom contains protons and neutrons with electrons in orbitals around the nucleas. I hope this helps. Let me know if anything is unclear.
Answer:
The answer would be at 120°C
