Universal Containers conducts evaluations of its sales reps using a custom object consisting of numerical scores and executive comments. The company wants to ensure that only the sales reps, their managers, and their manager's executives can view the rep's evaluation record, but the reps should not be able to view the executive comment fields on their review.
How can these requirements be met?

A custom field contains a feedback score which is on a scale of one to five. End users would like a visual indicator of one to five stars based on the number found in the feedback score custom field.
How can this visual indicator be displayed?

What should an app builder do to upgrade an unmanaged package that has been installed into production?

What sandbox is used for virtually any development, testing, or training purpose?

ABC Company has a custom object "Service" which has a lookup relationship to Account. ABC Company wants to enhance Salesforce1 with an action that allows account managers to enter a new service to an Account while looking at the account.
What should be done?