Salesforce Platform-App-Builder Based on Real Exam Environment

If an employee attempts to edit the description field after submitting an opportunity for approval, they will be presented with a ‘Record Lock’ notification. This means that the record is locked for editing while it is in the approval process and only users with the “Modify All” permission or users above them in the role hierarchy can edit it. [Source]

To start tracking how many shoe subscriptions have been sold for each shoe catalog, a roll-up summary field should be created. A roll-up summary field calculates values from related records on a master-detail relationship. It can count, sum, min, or max numeric values from child records on a parent record. 

 A summary report on the opportunity object should be created to add to the account page layout. A summary report groups rows of data by common values and allows users to create charts based on aggregate values. A summary report on the opportunity object can group opportunities by stage and display a chart of all related opportunities on the account detail page.

Partial Copy Sandboxes are ideal for testing and development purposes as they include a subset of production data and can be refreshed more frequently than Full Copy sandboxes.References:

Salesforce Help - Types of Sandboxes