✅ Correct Answer: Crocodile
Source: This question is taken from the Everyday Science
✅ Correct Answer: A gas
✅ Correct Answer: A class of nucleic acids
✅ Correct Answer: radio active gas
✅ Correct Answer: Mineral
✅ Correct Answer: smallest particle of an element which can undergo a chemical reaction
✅ Correct Answer: 5.972 × 1024 kg.