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Ответы@Mail.Ru: Поставить слова Им. п. мн.ч.:

Be careful, many words are pronounced in 2 ways (прожекторы-прожектора), but only one of them could be "approved". In normal speech (even if you speak in parliament) any way is acceptable. In documents, one could be called illiterate.

2015-06-15 10-57-31 прожектор.png