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.
REASON: To have a boat that will float in about six inches of water (with the outboard in up position). The purpose of this is to enable the boat to be launched at shallow-water launches, like those found on smaller lakes and more-remote waters.