Reaching last card in stack based on countdown timer

[Salinas, Ruben (GE Healthcare)]

I would like to code a timer that runs through a specified time, while the user is answering multiple choice questions (for a timed quiz). If the timer reaches zero, regardless of where the user is on the quiz (what question he /she is on), the application will automatically "shut down" and take the user to the final card where he/she will be presented with a score. Can you guys give me some ideas on how to code that timer and make it a global variable so I can continuously show it at the top of each question card?

Thanks in advance...

Harvjag