This is a 6 mark question.

Explain how the percentages of nitrogen, oxygen and carbon dioxide in the Earth’s atmosphere today have changed from the Earth’s early atmosphere.

In france, grapes are 1.95 euros per kilogram. what is the cost of grapes, in dollars per pound, if the exchange rate is 1.14 dollars/euro? (2.6)

16. why must the number of electrons lost equal the number of electrons gained in every redox reaction? use 3 – 4 sentences in your own words to address this question. 18. what type of radiation is emitted when chromium-51 decays into manganese-51? show the nuclear equation that leads you to this answer. 19. a radioactive nucleus alpha decays to yield a sodium-24 nucleus in 14.8 hours. what was the identity of the original nucleus? show the nuclear equation that leads you to this answer.

Which is true of a liquid? it has a definite volume but not a definite mass.it has a definite mass but not a definite volume.it has a definite volume but not a definite shape.it has a definite shape but not a definite volume.