Create Formula Fields

Part two (Customize Formula Fields) of the Create Formulas module asks for us to choose Region and Zone (and says it was set up in a previous unit) I am following the Prepare for Salesforce Admin Cert Path" and Region and Zone are not part of my drop down options and I dont know which unit to complete to find that as I have been doing the nits in order of the path. Any ideas?

https://trailhead.salesforce.com/content/learn/projects/customize-a-salesforce-object/create-formula-fields?trailmix_creator_id=strailhead&trailmix_slug=prepare-for-your-salesforce-administrator-credential

#Trailhead Challenges