You can view Questions (Add-On) revenue by a specific event by going to your Ticket Socket admin site and going to your event manager (Events > Events) and clicking on the event in question by clicking on the actions wrench and clicking "Edit".

While you are in the edit event page (See screenshot below)

• Click on Attendees
• Filter your search by Selecting Date Range (Today, Yesterday, Last 7, Last 30 or Custom Range)
• Select which tickets you wish to include into the search (General Admission filter used in screenshot)
• Click "Go" 
• Scroll down to "Questions Report" as seen in second screenshot

You can also export a .csv file to view this information in excel if you use this guide.