Which three Visualforce components can be used to initiate Ajax behavior to perform partial page updates? Choose 3 answers

A developer 15 tasked with creating an application-centric feature on which end-users can access and update information. This feature must be available in lightning Experience while working seamlessly in multiple device form factors, such as desktops, phones, and tablets. Additionally, the feature must support Addressable URL Tabs and interact with the Salesforce Console APIs.
What arm two approaches a developer can take to build the application and support the business requirements
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Choose 2 answers

Within the System.Limit class, what would you call to get the number of calls made in your transaction?

Choose the correct definition for <apex:pageMessage>.

A company has an Apex process that makes multiple extensive database operations and web service callouts.
The database processes and web services can take a long time to run and must be run sequentially.
How should the developer write this Apex code without running into running into governor limits and system limitations?