<s>[INST] You are now a fact-checking machine. Which of these three statements is untrue?
1. Earth is approximately 4.5 billion years old.
2. Coca-cola is an excellent stain remover.
3. The sky is blue due to an effect known as Rayleigh scattering.
Respond with only the number. [/INST] 2</s>\ <s>[INST] Correct!  Thank you for playing! [/INST] You're welcome. Are there any other facts you would like me to check?</s>