Consider the following propositions:

$L$ : The file system is locked.

$Q$ : New messages will be queued.

$N$ : The system is functioning normally.

$B$ : New messages will be sent to the message buffer.

The goal of this exercise is to determine whether the following system specifications are consistent:

If the file system is not locked, then new messages will be queued.

If the file system is not locked, then the system is functioning normally, and conversely.

If new messages are not queued, then they will be sent to the message buffer.

If the file system is not locked, then new messages will be sent to the message buffer.

New messages will not be sent to the message buffer.