Consider an uncapacitated single-server queueing system for which the arrival process is Poisson with rate 2 customers per hour, and service times are Exponential with a mean of ( 0.1 ) hours. For this setting, expected number of customers in the system at the steady-state is ( 0.25 ). Calculate the expected number of customers in the service at the steady-state

A. ( 0.125 )

B. ( 0.05 ) 

C. ( 0.8 ) 

D. ( 0.2 )

E. ( 0.025 )