There are two ways to tell if the timing belt has been replaced. One is obvious-you are looking at a service receipt showing the replacement.
Swimlane diagrams are used whenever you need to show activities, tasks, or process steps which are being performed by different actors/roles. You can use swimlanes to group activities in an activity diagram or process flow by any category what you need: by role, by system, by department, etc.
In the 1960s, Celanese also provided a public swimming pool, allowing anyone to swim for 25 cents a day. This was a great service, since this was one of the very few public pools in the area. In 1974, the Celanese establishes a Cytrel Tobacco Supplement plant in Cumberland with a peak capacity of 20 million lbs a year.