TerraChoice also measured green advertising in major magazines and found that between 2006 and 2009, the number mushroomed from about 3.5% of all ads to just over 10%; today, Case says, the number is probably higher still.
NASA bought hydrogen at 98 cents per gallon. A gallon of liquid hydrogen weighs 0.2679 kg, so they paid $3.66 per kg for liquid hydrogen. NASA bought oxygen at 67 cents per gallon. A gallon of liquid oxygen weighs 4.322 kg, so they paid $0.16 per kg for liquid oxygen. 384,071 gallons of liquid hydrogen in the external tank of the shuttle, for a cost of $376,389.58. ~141,750 gallons of liquid oxygen for a cost of $94,972.50. The total cost of all propellant for rocket fuel is $1,380,000. These numbers exclude the hydrogen and oxygen used for cooling, etc.
Multiply the total amount of fuel per month you burn by the cost of a gallon or liter of gasoline to get your monthly fuel costs. If gas costs $4 per gallon ($1.05 per liter), you spend $128 per month on fuel, or 17 cents per mile (10 cents per km).. Divide the number of miles or kilometers you drove by the number of gallons or liters it took to refill your tank. For example, if you drove 300 miles (482.8 km) and burned 15 gallons (56.78 liters) of gasoline, your vehicle got about 20 miles per gallon (8.5 km per liter).