Article Writing / Rewriting needed

I work for a large SEO company and we are trying to write content for a large number of websites all at once, and I could use some help. I have articles that need writing, and articles that need rewriting, and they are on various subjects. Please specify the following information in your bid: * What is your price per article of 400-500 words length? * How many articles can you complete in the span of 24 hours? * How soon can you begin? Please attach samples if you have them, otherwise I will give you a sample to write on. Anyone who can start right now will be given preference.