Universal containers wants to ensure that they are accepting clean data from their users and verify that important fields are entered. What should an app builder recommend to meet this requirement?

Universal Containers would like sales reps to get permission from their managers before deleting Opportunities.
What can be used to meet these requirements?

How would you ensure that records of a particular object are visible only to the user, and users higher in the role hierarchy? choose 2 answers.

You are building a project mgmt app. According to the design given to you, a project must store info regarding the various functional modules under it. Each functional module must store info regarding responsibility assigned to each developer. Info about the responsibility must have info about the due date and status.
What could be the most optimal model to achieve this?

A custom object has a Public Read Only sharing setting that does not grant access using hierarchies. A dynamic sharing rule provides Write access to the object to the Global Marketing public group if the record is marked as Global. A user creates a new record and marks it as Global.
Who will have write access to the record?