Which is a true of a molecule? A bond of 2 different types elements
Does not contain a bond
A bond of 2 or more of the same element

The correct answer is a

1. and 2. question: in which equation? or i don't understand you, 3. a), 4. c), 5. c), 6. b), 7. d), 8. d) if small number is underlined(behind symbol) , b) if big number is underlined(in front of symbol)9. what is underlined there? 10. c)

D.na is the answer hope this

The correct answer is "atomic weight".