Distribution Lists and cell contacts


I have two questions regarding contacts and automation...

1) When setting up an automated workflow, instead of entering for example 25 individual emails (sending to specific people), can you enter a distribution list? Many times we need automated workflows to go to be sent to a large group of individuals. Entering that many individual email addresses is time consuming.

Additionally, I was told in a recent Smartsheet training that if you have more than 20 contacts in a single cell, the automation won't work...? Is this true, as well?