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.
The swim cap is a piece of equipment that provides multiple benefits. For professional swimmers, swim caps reduce drag to increase speed in the water. Swim caps also keep hair out of the face, help reduce the effects of chlorine on the hair and help swimmers retain body heat when they are swimming in colder water.