The answer is :A) You would go through one sort of material, and then a different, denser material, and then a still-different, still-denser material, because the planet is made of concentric layers, sort of like an onion.
I would say that the resource you could use to find the meaning of <em>ambiguous </em>is the dictionary.
An almanac is an annual publication about weather, crops, etc.
A thesaurus is a dictionary of synonyms.
An encyclopedia is self-explanatory.
Answer:
The natural gas is used more often because it is much more environmentally friendly.
Explanation:
Most of the world, in order to produce energy for whatever purpose, mostly relies on usage of fossil fuels. The fossil fuels that are the most dominant when it comes to usage are unfortunatelly the ones that cause the most pollution. Those two fossil fuels are the coal and oil. There is another fossil fuels though that has always been in the background but is gradually becoming more and more popular.
The fossil fuel that starts to gain more ground is the natural gas. The natural gas is relatively abundant, easy for usage, transportation, and economically justifiable. What is also very important and gives it an advantage lately is the fact that the pollution form it is uncompearably lower, in fact, the methane that is released from the natural gas only does so because of leaks during its transportation.
