Jerry is working on a research project about the effectiveness of social media marketing. He found some sources with information relevant to his project, and he's trying to determine which ones are credible. Which THREE sources should he select to use for his project?

1. a journal article titled "Marketing Strategies: Social Media" by a university professor

2. an article titled "Tips for Effective Social Media Marketing" on a government agency website

3. a social media post promoting a new product launched by a reputable business

4. a business magazine article titled "Why Social Media Marketing Works" by a journalist

5. a blog post titled "My Social Media Marketing Success" by an unknown author

(Pick THREE answers form 1,2,3,4 and 5)