Need an expert in JAVA to explains to me what is happening in the program PLEASE STEP BY STEP

Queue: (JAVA)

Q4: A program performs the following operations on an empty queue Q:

n. Q.enqueue(24)

o. Q.enqueue(74)

p. Q.enqueue(34)

q. Q.first()

r. Q.dequeue()

s. Q.enqueue(12)

t. Q.dequeue()

Please show the queue contents at the end of these operations. Clearly show the front and rear of the queue.