A developer wants to build an audience by identifying subscribers who opened a specific email. Which query should the developer use?

How many month of data can a developer query from the tracking data views (_Sent, _Open, _Click)?

A developer is creating a custom preference center and wants to log unsubscribe events from the CloudPage. Which set of parameters should be captured and provided to the LongUnsubEvent Execute Call to ensure accurate unsubscribe information?

NTO is using an asynchronous SOAP API call to the TriggerSend object to send order confirmation email to their customers. Which API object and attribute should be used to retrieve the status of the API call?

A developer is making an API REST call to trigger an email send. An access token is used to authenticate the call.
How long are Marketing Cloud v1 access tokens valid?