Is there another way to say common defense?

security

What two things are being compared in this epic simile (the odysseus)

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.

In what way did expansion and global trade during the 15th to 18th centuries affect the economies of european countries?