Imagine that it takes an average Australian miner 10 hours to mine a metric ton of coal and 20 hours to mine a metric ton of manganese. It takes the average South African miner 4 hours to mine a metric ton of coal and 12 hours to mine metric ton of manganese.

a. Create a table to show how productive each miner is in a day. 

b. For each miner, calculate the opportunity cost of mining a ton of coal and a ton of manganese. 

c. In what task does each miner have a comparative advantage? 

d. Which resource will each country import? How about export? 

e. Explain how markets provide the opportunity for the mining companies to specialize and earn gains from trade.