Smashing Pumpkins song: "Bored by the chore/of saving face"?

Questions

What is Bok Choy?

Which country does Luxembourg share a border with?

In which city is the Dome of the Rock Mosque?

What is the name of the classical rotunda which was built as a pagan temple in Rome and is now a Christian place of worship?

What is the name of the American architect who designed the house named Falling water which was built in 1936-7 in Bear Run Pennsylvania?