10.) 69% of all copper atoms are Cu-63. How many times more massive than an atom of C-12 is an atom this copper isotope?

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)

0.50 hope this  

The answer is b because c don't explain why the moths are on them and it isn't a because as we know only one species of moth does this