Consider an Espresso Stand with a Single Barista

Multiple Choice

Consider an espresso stand with a single barista.Customers arrive at the stand at the rate of 28 per hour according to a Poisson distribution.Service times are exponentially distributed with a service rate of 35 customers per hour.The probability that there are exactly 3 customers in the system is

A) 0.0000
B) 0.1024
C) 0.4096
D) 0.5120