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.
Firstly, it can suspend the bait at a predetermined depth; secondly, due to its buoyancy, it can carry the baited hook to otherwise inaccessible areas of water by allowing the float to drift in the prevailing current; and thirdly, a float also serves as a visual bite indicator.