Which API can be used to execute unit tests? (Choose three.)

In an organization that has multi-currency enabled, a developer is tasked with building a Lighting Component that displays the top ten Opportunities most recently access by the logged in user. The developer must ensure the Amount and LastModifiedDate field values are displayed according to the user's locale.
What is the most effective approach to ensure values displayed respect the users locale settings?

What is the correct syntax for calling a controller action from a Visualforce page and updating part of the page once the action is completed? (Choose two.)

What is the transaction limit for the number of DML statements allowed?

A business process requires sending new Account records to an external system. The Account Name, Id, CreatedDate. and CreatedByld must be passed to the external system in near real-time when an Account is Inserted without error.
How should a developer achieve this?