Which of the following rivers form international boundaries between the united states and its neighbors?
a.
the mississippi and the colorado
b.
the ohio and the missouri
c.
the rio grande and the st. lawrence
d.
the illinois and the columbia

Which of the following describes an effect of world war ll on the united states economy a. automobile companies produced a record number of cars b. many factories had to expand to produce military equipment c. the airplane industry suffered as the allies began using airplanes in combat d.cities with shipyards declined because so many ships had been sent overseas.