Read the text and answer the question. FROM THE HISTORY OF PETROLEUM Petroleum and natural gas have been known to man long before our era. Petroleum production on an industrial scale, however, was started only a little more than one hundred years ago,

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FROM THE HISTORY OF PETROLEUM



Petroleum and natural gas have been known to man long before our era. Petroleum production on an industrial scale, however, was started only a little more than one hundred years ago, while the production and use of natural gas - only in the present century.

Formerly, petroleum was extracted by most primitive methods, i.e. by digging wells to the petroliferous strata where the petroleum was still in the liquid state. Cases are known when surface seepages of petroleum were so considerable that it accumulated in the depressions of the relief forming petroleum lakes. But in these cases the petroleum with time lost its volatile components and turned into asphalt. As can be seen from ancient historical documents the use of petroleum as fuel dates back to extremely early times. Not only liquid petroleum but asphalt was also used as fuel.

The use of petroleum in early times refers to the Apsheron peninsula and other regions of the Caspian shores which abounded in petroleum and where there was the deficiency of other kinds of fuel (coal, peat, wood), this forced the inhabitants to use petroleum as fuel for heating their dwellings, cooking purposes, etc.



What was petroleum used in early times for?


Выберите один ответ:
a. Petroleum was also used for refining mineral products.
b. Petroleum was also used for repairing equipment
c. Petroleum was also used for heating their dwellings, cooking purposes and as fuel.