In a typical SSL setup involving a trusted party and trusting party, what consideration should an Architect take into account when using digital certificates?

Universal Containers (UC) has an existing web application that it would like to access from Salesforce without requiring users to re-authenticate. The web application is owned UC and the UC team that is responsible for it is willing to add new javascript code and/or libraries to the application. What implementation should an Architect recommend to UC?

Universal Containers (UC) would like to enable self-registration for their Salesforce Partner Community Users.
UC wants to capture some custom data elements from the partner user, and based on these data elements, wants to assign the appropriate Profile and Account values.
Which two actions should the Architect recommend to UC? (Choose two.)

Universal Containers (UC) would like its community users to be able to register and log in with Linkedin or Facebook Credentials. UC wants users to clearly see Facebook &Linkedin Icons when they register and login.
What are the two recommended actions UC can take to achieve this Functionality? Choose 2 answers

Universal Containers (UC) uses Active Directory (AD) as their identity store for employees and must continue to do so for network access. UC is undergoing a major transformation program and moving all of their enterprise applications to cloud platforms including Salesforct, Workday, and SAP HANA. UC needs to implement an SSO solution for accessing all of the third-party cloud applications and the CIO is inclined to use Salesforce for all of their identity and access management needs.
Which two Salesforce license types does UC need for its employees'
Choose 2 answers