After a Platform Event is defined in a Salesforce org, events can be published via which two mechanisms? Choose 2 answers

A developer needs test data for Apex test classes.
What can the developer use to provide test data to the test methods? (Choose two.)

If you have a method "doStuff(List<sObject> records)", which is a valid call?

Universal Containers stores user preferences in a Hierarchy Custom Setting, User_Prefs_c, with a Checkbox field, Show_Help_c. Company-level defaults are stored at the organizational level, but may be overridden at the user level. If a user has not overridden preferences, then the defaults should be used.
How should the Show_Help_c preference be retrieved for the current user?

A company wants to incorporate a third-party web service to set the Address fields when an Account is inserted, if they have not already been set. What is the optimal way to achieve this?