Trade allows a country to consume outside its production possibilities frontier.

People are fascinated by storms, even when they are nowhere near them. A possible explanation for this is that we may be addicted to the danger. Because early experiences of humans involved constantly perilous conditions, we developed a certain expectation of risk. In the modern environment, we are not exposed to natural risks in the same way, but the underlying neural mechanisms have not gone anywhere. Therefore, most of us enjoy a certain thrill. A storm approximates this thrill. It is powerful and even dangerous. But safely hidden inside and in front of our computer screens, we do not think it will really hurt us. By taking this relatively minor risk, we satisfy our inner risk seeker without going into dangerous territory. As for those people following a storm avidly even when they were far away from it, risk can well be experienced vicariously.

A、the consumer can rank all possible consumption bundles.

B、more of a good is always better.

C、the consumers can rank all affordable consumption bundles.

D、all preferences conditions are met.

A. Bills of Lading            B. Sea Waybills

C. Manifests              D. Shipping Notes

A、right; rises

B、right; falls

C、left; falls

D、left; rises