6. Определите значение выделенных слов по сходству их корней с корнями соответствующих слов в русском языке:

natural gas, gas consisting of methane, organic materials, energy sources, bottle of soda pop, disposal problem, active oil field, formation of gas field, developing technology, synthetic gasoline, amounts of ethane, propane, butane and pentane, can be transported, pure product, supercritical conditions, elemental sulfur.