$2$

$14$ points

$($a$)(4$ points$)$ In the Kendall Queuing System Notation $($X$/$X$/$x$/$X$),$ what do the first

four terms stand for?

$($b$)$ An IT help desk is available $8$ hours a day, with a single person to provide help.

Assume the average exponentially distributed service time for each person needing

help is $10$ minutes, and there are $4$ arrivals an hour.

i$.(3$ points$)$ How long on average will each person have to wait in the queue?

ii$.(3$ points$)$ How many IT specialists will need to be provided to prevent anybody

queueing?

iii. $(2$ points$)$ What critical assumption does the answer to part ii depend on$?$

iv$.(2$ points$)$ At what particular time of the day is this assumption likely to be

incorrect?