Travelers arrive at the main entrance door of an airline terminal according to an exponential inter arrival time distribution with mean 1.6 minutes. The travel time from the entrance to the checkin is distributed uniformly between 2 and 3 minutes. At the check-in counter, travelers wait in a single line until one of the five agents is available to serve them. The check-in time (in minutes) follows a Weibull distribution with parameters b = 7.76 and a = 3.91. Upon completion of their check-in, travelers exit to their gates. 

a. Create a simulation model, including animation, of this system. Run the simulation for ten 16-hour shifts to determine the average time in system, average number of passengers completing check-in, and the average length of the check-in queue. 

b. Modify the foregoing model by adding agent breaks. The 16 hours are divided into two 8-hour shifts. Agent breaks are staggered, starting at 90 minutes into each shift. Each agent is given one 15-minute break. Agent lunch breaks (30 minutes) are also staggered, starting 3.5 hours into each shift. Compare the results of this model to the results without agent breaks.