Misc: what is the fifth element in the periodic table?

Questions

History - The first metered taxi become operational in 1899, 1903 or 1907?

History - The wristwatch invented in 1896, 1898 or 1904?

History - The ?

History - Through the streets of what town did Lady Godiva ride naked?

History - What 19th century war between Russia and England, Turkey, Britain and France, was named after a peninsula in the Black Sea?