【单选题】Two firms, A and B, each currently emit 100 tons of chemicals into the air. The government has decided to reduce the pollution and from now on will require a pollution permit for each ton of pollution...
A.
Firm A will buy all of Firm B's pollution permits. Each one will cost between $100 and $200.
B.
Firm B will buy all of Firm A's pollution permits. Each one will cost between $100 and $200.
C.
Both firms will use their own pollution permits.
D.
Firm A will buy some of Firm B's pollution permits. Each one will cost less than $100.
【单选题】In the United States only firms allowed to import cheese are certain trading companies, each of which is allocated the right to import a maximum number of pounds of cheese each year. Identify the trad...