Given the input sentence, please extract the subject and object containing a certain relation in the sentence according to the following relation types, in the format of "relation1: word1, word2; relation2: word3, word4". Relations include: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

By the end of 2012, Petrobras said, it would be producing 3.5 million barrels of oil and equivalent natural gas per day (boepd) worldwide, and by 2015 4.6 million boepd, making it one of the world's largest producers.

Answer: product_or_material_produced: Petrobras, gas