+ Ammo equals 0
Set Timescale to 0 (this pauses the game)
Pop the dialog box (you'll have to write events for that yourself, normally it is enough to pop a Panel object and draw text on top, with some pictures)
++ Answer is correct (condition to check whether the player answered correctly)
> Set Ammo to 100
> Set Timescale to 1 (this resumes the game at normal speed)
> Destroy dialog box (a little cleanup)
++ Answer is incorrect
> Ridicule the player (next time Ammo will still be 0, so another dialog box will appear)
> Destroy dialog box
In a nutshell.