title: Add timestamp in adjacent cell when cell equals a specific value
body: <p>I have a project tracker tool. Column K has a drop down menu for when a Task is completed. The drop down menu has the option of setting the task as "Not Delivered" or "Delivered". I would like to program Column L so that whenever someone chooses a task as "Delivered", I have a timestamp of that action. Any help would be appreciated. </p>