Explanation
A list view is a feature that allows users to filter and display records based on certain criteria and fields. A Kanban view is a feature that allows users to view records as cards organized by columns that represent stages in a process such as opportunity stages or case statuses. Users can switch between list view and Kanban view by clicking on a toggle button on any object tab that supports Kanban view such as opportunities or cases.
Users can also edit records by dragging and dropping cards from one column to another or by clicking on an inline edit icon on each card. In this case, the administrator can create a list view on the opportunity object that filters opportunities by expected close date in the next 90 days; and recommend users switch the view to Kanban to edit opportunities by drag and drop. References:
https://help.salesforce.com/s/articleView?id=sf.lex_list_views.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.kanban_view.htm&type=5

Explanation
Knowledge articles are documents that provide information or solutions about products, services, or processes in Salesforce. You can use knowledge articles to respond to customers quickly and consistently with accurate information. You can create different types of articles with different templates and fields, such as FAQ articles, troubleshooting articles, how-to articles, etc. To meet the requirement of responding to customers with the top five troubleshooting tips that could help solve their issue, you need to create knowledge articles with those tips and attach them to your email responses or case comments. References:
https://help.salesforce.com/s/articleView?id=sf.knowledge_article_types.htm&type=5

Explanation
To require users to choose a specific search engine from a picklist when lead source is "Search Engine", and hide it otherwise, the administrator should create a picklist for specific search engine on the same screen as lead source, and set conditional visibility so that it is only shown when lead source is "Search Engine". This will make sure that users see only relevant fields based on their input. A decision element will create an extra screen that may disrupt user experience. An assignment element will not affect field visibility. A validation rule will not hide fields but only show errors when values are invalid. References:
https://help.salesforce.com/s/articleView?id=sf.flow_ref_elements_screen_components_picklist.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.flow_ref_elements_screen_components_conditional_visibility.ht

Explanation
A scheduled flow is a type of flow that runs at scheduled times on batches of records that meet certain criteria.
It can be used to count the number of open cases associated with each account and update the account with this value every Friday evening by using an assignment element to loop through the accounts and cases and assign the count value to a field on the account record. Using a record trigger flow, a scheduled process builder, or a roll-up summary field are not suitable options for this requirement because they would not run at scheduled times or on batches of records; they would run every time a record is created or updated, which may not reflect the accurate count of open cases at the end of each week. References:
https://help.salesforce.com/s/articleView?id=sf.flow_concepts_scheduled.htm&type=5

Explanation
Two data loss considerations when changing a custom field type from Text to Picklist are:
Assignment and escalation rules may be affected, because the values in the picklist may not match the values that were previously entered in the text field, and the rules may not trigger as expected.
Any list view based on the custom field is deleted, because the filter criteria for the list view may not be valid for the new field type, and the list view cannot be displayed. There will be no data loss with use of a global value set or auto updates to Visualforce references, because these are not related to changing a custom field type from Text to Picklist. References:
https://help.salesforce.com/s/articleView?id=sf.fields_changing_type_considerations.htm&type=5