You are managing a software company which delivers an online content management system to its

users. You want to better understand your workflow in order to check if you can save time on bug

fixing and maintenance operations.

You are analysing the following workflow:

users submit bug reports

your software engineers analyse and prioritise bugs

the bugs are fixed and new versions are deployed

$($a$)$ Write a delay based model that describes this workflow.

$($b$)$ Which order is your model?

$($c$)$ Assuming that users report $20$ bugs$/$malfunctions$/$requests per week on average, that it takes $1$

hour per request to process and prioritise it and that on average each fix requires $5$ hours of work

of an experienced engineer, what is the total number of items that are being processed in your

system at any time?