How many picograms are in 1 mg? in 35 ng?

1mg = 1e+9 = 1,000,000,000 picograms
35ng = 35,000 picograms

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)can be increased in a closed system