What is true regarding changing the field type of a rich text area?

An admin is trying to add a custom VF page to the mobile app quick navigation menu but can't. What might be the problem?

Which two are a capability of record types? Choose two answers

Ursa Major Solar's sales team has been struggling to enter data on mobile since rollout; the team dislikes scrolling through all of the fields to input only the necessary data.
How could the app builder solve this with minimal impact to desktop users?

Universal Containers has a requirement that an Opportunity should have a field showing the value of its associated account's billing state. This value should not change after the Opportunity has been created. What is the recommended solution to configure this automation behavior?