It depends on the list that you have. The more directory submission sites that you have the better, but don't just settle for it since you can also do forum posting, blog commenting and social bookmarking.
Domain authority is a measure of the power of a domain name and is one of many search engine ranking factors. Domain authority is based on three factors: Age, Popularity, and Size.
SEO gurus Moz can be credited with the metric known as DA or domain authority. Moz’s own search algorithm gauges the quality of any given site based on a huge complex combination of factors including onsite and offsite, taking in to account things such as diversity of Backlinking domains to come up with a score between 0 and 100. A brand new site, for example, will have 0 whereas a very high authority site might have 80/100. Domain Authority gives those working in the field of online marketing a useful metric by which to consider the apparent quality of any site.
Try to visit moz so you will get familiarize with it.