Assuming you're using DMS, you should be able to configure goals that correspond to each header section. You may have to trigger the completion of the goal in code:
if (Sitecore.Analytics.Tracker.IsActive && Sitecore.Analytics.Tracker.CurrentPage != null)
{
PageEventData eventData = new PageEventData("My Goal Name");
eventData.Data = "this is some event data.";
VisitorDataSet.PageEventsRow pageEventsRow = Sitecore.Analytics.Tracker.CurrentPage.Register(eventData);
Sitecore.Analytics.Tracker.Submit();
}
Then you just have to look at your reports to see how effective each FAQ section is.
Hope this helps.