System admin - wants to make sure that when opportunity is close - nobody can modify it.

SFB Industries need to create a relationship between two objects. They need to have their own independent security settings but if a child record has a parent, the parent CANNOT be deleted. How can this be achieved?

What tool can be used to deploy sandbox to 2 different Orgs ?

The administrator at Cloud Kicks needs to import a batch of person accounts into Salesforce.
What tool should the administrator use?

The administrator of Universal Containers is testing an approval process in a recently refreshed Developer Pro sandbox and is finding that none of the notification emails are being sent to the approvers.
Which two reasons could be the cause? (Choose two.)