What sandbox type allows for the use of a sandbox template?

UVC uses a custom object to track open job positions. They would like to automatically post updates on a record's feed whenever a position stage is changed. Which social feature can be used to accomplish this.

Universal Containers wants to understand return on investment for the latest advertising buy. They currently use a private security model for all objects.
What should an app builder recommend?

ABC Company has a custom object "Service" which has a lookup relationship to Account. ABC Company wants to enhance Salesforce1 with an action that allows account managers to enter a new service to an Account while looking at the account.
What should be done?

What should an app builder consider when choosing a template for a new Lightning record page?