In 'The Big Bang Theory', in which city do the characters live?

Who played Spock in the original 'Star Trek' series? Who played Captain Jean-Luc Picard in 'Star Trek: The Next Generation'? What is the name of the time machine in 'Doctor Who'? Which streaming service launched 'The Mandalorian' in 2019? In 'The Big Bang Theory', which character says "Bazinga!"? Who played Sheldon Cooper in 'The Big Bang Theory'? Which 'The Big Bang Theory' spin-off follows Sheldon's childhood in Texas? In 'How I Met Your Mother', who is the narrator telling the story to his kids?