I have these questions for home work at university
1.how much energy would a barrel of mazut produce and how much volume of natural gas is needed for the same amount of energy to be produced?

2.how much would a barrel of mazut cost and how much would be the respective cost (for the production of the same amount of energy) of natural gas ?

3. How much energy does a mobile phone/cell phone which is fully charged every second day consume ?

4. How many years would two billions (UK)/trillions (USA) cubic feet of natural gas last assuming an annual consumption of 30TWh?

Please if someone can help me answer above questions or some of them, please send to >Removed<

Sounds straightforward enough, but you'll need to do a lot of research to find the appropriate information.
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