Which feature should a developer use to update an inventory count on related Product records when the status of an Order is modified to indicate it is fulfilled?

Which type of code represents the Model in the MVC architecture on the Force.com platform?

A developer needs to import customer subscription records into salesforce and attach them to existing account records. Which 2 actions should the developer take to ensure the subscription records are related to the correct account records? Choose 2 answers

Which type of code represents the Model in the MVC architecture when using Apex and Visualforce pages?

A Visualforce page is required for displaying and editing Case records that includes both standard and custom functionality defined in an Apex class called myControllerExtension.
The Visualforce page should include which <apex:page> attribute(s) to correctly implement controller functionality?