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 code segment can be used to control when the dowork() method is called?

The operation manager at a construction company uses a custom object called Machinery to manage the usage and maintenance of its cranes and other machinery. The manager wants to be able to assign machinery to different constructions jobs, and track the dates and costs associated with each job. More than one piece of machinery can be assigned to one construction job.
What should a developer do to meet these requirements?

An org has different Apex Classes that provide Account -related functionality.After a new validation rule is added to the object, many of the test methods fail.What can be done to resolve the failures and reduce the number of code changes needed for future validation rules?Choose 2 answers:

What are three ways for a developer to execute tests in an org? Choose 3.