
Explanation

Box 1: Yes
The question states that User1 is synced to Azure AD. This tells us that the short password (Pass) meets the on-premise Active Directory password policy and you were able to create the on-premise account for User1.
The on-premise Active Directory password policy applies over the Azure AD password policy for synced user accounts.
Box 2: No
Self-Service Password Reset would need to be configured.
Box 3: Yes
The password for the Azure AD User1 account will expire after 90 days according to the Azure AD password policy. If the on-premise password policy has a shorter password expiration period, User1 would have the change his/her on-premise AD password. The new password would then sync to Azure AD.
Reference:
https://docs.microsoft.com/en-us/azure/active-directory/hybrid/how-to-connect-install-express