Who cares? Carbon emissions aren't causing "global climate change" anyway. The earth's climate has changed dramaticly in the past way before there were any man-made machines. It's doing it again regardless of what we humans do or don't do.
You must determine how many grams are in a tonne. You then must then use the molecular weight of carbon to determine the moles of carbon in that many grams (i.e. (grams C)/(M.W. of C)). As there is...