Aperiod of détente with the soviet union ended with the
a.
truman doctrine.
b.
cuban missile crisis.
c.
soviet invasion of afghanistan.
d.
yalta conference.

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