Global warming is attributed to, in part, increasing
concentrations of CO2 in Earth’s atmosphere as a direct result of
human activity. For example, in the period from 1751 to 1900, about
44 gigatonnes of CO2 was released by burning of fossil fuels; in
the period of 1901 to 2008 that number skyrocketed to 1244
gigatonnes.

Using the information given here, calculate the number of
gallons of gasoline (octane, C8H18) that must be burned to release
1244 gigatonnes of CO2 into Earth’s atmosphere.

2C₈H₁₈ (l) + 25 O₂ –>
16CO₂ (g) + 18H₂O (g)

1 gigatonne = 1 x 10¹⁵ g

density of C₈H₁₈ = 2661g/gallon

A) 1.517 x 10¹⁴ gal *Correct one, but I am
not sure how to get to this answer.*

B) 1.213 x 10¹⁵ gal

C) 5.844 x 10¹³ gal

D) 1.010 x 10¹⁶ gal