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Why did countries not allow jewish refugees asylum?

What is the meaning of the phrase “bear ’t”? what word is left out between the words but and few?

One drawback of voluntary trade is that it a. requires two groups to use a common language b. can make one group dependent upon another for necessary goods c. doesn't occur unless there is a shortage of goods for at least one group d. forces groups to rely on themselves to produce all the goods they need