In which century did columbus first sail into the western hemisphere?
a. the 13th century
b. the 14th century
c. the 15th century
d. the 16th century

c. the 15th century

Explanation:

Christopher Columbus was an Italian-born navigator and explorer who sailed for the Crown of Castile (Spain) and discovered the New World. Columbus was trying to find a route through the ocean that would enable Europeans to trade with Asia. His first journey took place in 1492, while the last one took place in 1502. 1492 corresponds to the 15th century (1401-1500).

all choices are correct

the correct answer option is: weapons.

explanation:

tensions rose as the two opposing superpowers competed for 'weapons'.

referring to the cold war (1945-1991), the two superpowers, usa and ussr, experienced a phase of struggle and conflict with each other. these two superpowers considered each other as a threat to their survival and thus opted for policies to strengthen their positions.

the two superpowers never went to war with each other directly but competed for weapons to preserve their positions.