Develop and draw a Petri Net model to explore the security of a classroom with one door,

similar to the classroom in which this class is held (except for the number of doors). The

door can only be "open" or "locked", and a key is needed to open or lock the door. The

conditions (places) that can hold are:

P1: door is open and person without key is inside the classroom

P2: door is open and person without key is outside the classroom

P3: door is locked and person without key is inside the classroom

P4: door is locked and person without key is outside the classroom

The events (transitions) that can occur are:

T1: person without key enters the classroom

T2: person without key leaves the classroom

Explore the following initial markings:

M = (1, 0, 0, 0)

M = (0, 0, 1, 0)