Explanation

Box 1: Yes
The BookInPolicy allows the Managers group. User1 is in the Managers group so User 1 can book ConferenceRoom1 automatically without the approval of User4.
Box 2: No
The BookInPolicy allows the Managers group. User2 is not in the Managers group so User 2 cannot book ConferenceRoom1 automatically without the approval of User4.
Box 3: No
The RequestInPolicy does not include User4. Therefore, User3 is not allowed to request to book the meeting room either with or without approval.
Reference:
https://docs.microsoft.com/en-us/powershell/module/exchange/set-calendarprocessing?view=exchange-ps