Did the southern states have Constitutional authority to secede?

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 of the following is not a requirement to become a us representative (congressman/congresswoman)?

What were some effects in world war 1 in europe ? ( and only in europe)