A producer and a consumer threads are sharing a buffer as shown below. The buffer is initialized with blank characters in each position. Semaphores A, B, and C are used to protect the buffer and are initialized properly. After the threads have been running for a while, the buffer appears as shown below and the threads are executing at the location shown by the arrows below. If the last character placed in the buffer was d and the value of semaphore A is 4, answer the questions below.

a

t

x

y

j

c

b

f

u

d

w

q

Consumer	Producer
Do other calculations <----------	P(B)
P(A)	P(C)
P(C)	Place item in buffer
Read item from buffer	V(C)
V(C)	do other caclulations <---------
V(B)	V(A)

a)What was the value of semaphore B when it was initialized? ______________

b)What is the value of semaphore B now? ________________

c)What was the value of semaphore C when it was initialized? _______________

d)Which specific characters, those are still in the buffer, HAVE BEEN READ by the consumer? _________________

Please please not just anwser -- really looking for explanation!