A japanese worker can make 30 cars or 5 planes in a year. a u.s. worker can make 50 cars or 10 plane

A Japanese worker can make 30 cars or 5 planes in a year. A U.S. worker can make 50 cars or 10 planes. Answer the following questions:
a) Who has an absolute advantage in cars? in planes?
b) What is Japan's opportunity cost for cars? For planes? What is the U.S' opportunity costs for cars? for planes?
c) Who has a comparative advantage in cars? in planes?
d) Should Japan and the U.S. trade and if they do who specialize in each good?
e) Does everyone gain with the two countries trading? Explain your answer.

What do mean by all these questions? Japanese workers are not productive?