Answer: a). Spain
b). none
c). 2.4
Explanation: a). Absolute advantage occurs when a country produces more of a good than the other country. In this case, Spain produces 50 units of Tractors while, Bolivia produces only 30 units of Tractors. Thus, Since Spain is producing more it has an absolute advantage in Tractors.
b). Both the countries are producing equal units of Cotton. Thus, we can say that none of them has an absolute advantage in cotton production.
c. Opportunity cost is the cost of the lost alternative. When Spain produces Tractors it is sacrificing production of Cotton. So, opportunity cost on 1 unit of Tractor will be,
Thus, 2.4 units of cotton which is given up is the opportunity cost of Spain for producing 1 unit of Tractor.