Question

1 ) petroleum is also called ________?
2) ___________combustion is less polluting .
3) In 1992.,__________nations signed an agreement on biodiversity.​

Answer 1

1)petroleum is also known as black gold

Answer 2

Answer:

1)Petroleum, also called crude oil, is a fossil fuel.

2)Diesel engines combustion is less polluting.

3)In 1992, Rio Earth Summit nations signed an agreement on biodiversity

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