<Tr> <Th> Products </Th> <Td> Crude Oil, Gas, petroleum products, petrochemicals, </Td> </Tr> <Tr> <Th> Website </Th> <Td> www.nnpcgroup.com </Td> </Tr> <P> The Nigerian National Petroleum Corporation (NNPC) is the oil corporation through which the federal government of Nigeria regulates and participates in the country's petroleum industry . </P> <P> NNPC was established on 1 April 1977 as a merger of the Nigerian National Oil Corporation and the Federal Ministry of Mines and Steel . NNPC by law manages the joint venture between the Nigerian federal government and a number of foreign multinational corporations, which include Royal Dutch Shell, Agip, ExxonMobil, Chevron, and Texaco (now merged with Chevron). Through collaboration with these companies, the Nigerian government conducts petroleum exploration and production . In 2007, the head of the Nigerian wing of Transparency International said salaries for NNPC workers were too low to prevent graft . </P>

What are the functions of nnpc in nigeria
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