What triggered the first opium war

Which of the following was used only once, to ratify the 21st amendment (repealing prohibition)? a. three-fourths of both houses of congress. b. three-fourths of the state legislature approved it. c. two-thirds of the state legislature approved it. d. ratifying conventions in three-fourths of the states approve it.

Which fact would this be, and how might you verify the truth?

How did geography influence the development of the byzantine empire?