Consider a single server queue with a Poisson arrival process at rate \, and exponentially distributed service times with rate µ. All interarrival times and service times are independent of each other. This is similar to the standard M|M|1 queue, but in this queue, as the queue size increases, arrivals are more and more likely to decide not to join it. If an arrival finds n people already in the queue ahead of them (including anyone being served), then they join with probability 1/(n+1). Let N(t) be the number in the queue at time t. (c) Find the equilibrium distribution for this queue, when it exists. (d) What are conditions on A and under which the equilibrium distribution exists?