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VI. Test Your Understanding of the Words:

“is eliminated” in the last sentence means:

(a) is deleted (c) is cut

(b) is included (d) is excluded

VII. Word Choice.

Find the most suitable word to complete the following
sentence:

Petroleum is worth seeking even
if the processes of oil and gas
generation, migration and entrapment
are:

(a) incomprehensible (c) unrealizable

(b) inevitable (d) irreversible

Варіант 2.

Petroleum is a natural substance that occurs in the Earth as
semi-solids, liquids, or gases-or mutual solutions of these. There
are two types of petroleum liquids: crude oil, which leaves a
residue of compounds of high molecular weight on distillation, and
gas condensate, which leaves no residue on distillation. Petroleums
are mixtures of hydrocarbons (compounds of hydrogen and carbon
only) usually with some contaminant non-hydrocarbon compounds
of nitrogen, sulphur and oxygen in small amounts; also of
vanadium and nickel. The hydrocarbons form a great range of
compounds, and each accumulation of oil and most accumulations
of gas are unique in that they differ in the proportions of the
constituent hydrocarbons and the contaminants. They differ also in
that each hydrocarbon compound may have the atoms of its
molecule arranged in two or more different spatial arrangements,
called isomers. The isomers of a compound differ slightly in