A．people used to prefer gold and silver as their medium of exchange
B．money was invented first in Europe and then in Asia
C．coins appeared as the result of inconvenience in exchange
D．the earliest coins were made quite differently from those we are using now

A．China was the first country to use coins in the history of human being.
B．The coins were used in China more widely than European countries.
C．All the Chinese coins, though different in shape, had the pierced hole.
D．Bronze was the only ideal material used to make coins in the early time.

A．the Ming coin cannot be found again
B．"Knife of Ming" was nothing but the inscription on the coin
C．the shape of the Ming coin was still like a knife
D．there is not any change to the design of the Ming coin

A．how to distinguish a Greek coin from a Chinese one
B．how to recognize the exact age of Chinese coins
C．the appearance of "cash" in China
D．the development of coins in ancient Greece

A．not fearing stress
B．knowing the art of relaxation
C．high sense of responsibility
D．having control over performance

A．making a choice between "flight and fight"
B．reaction to cases both chemically and physically
C．responding to crises quickly
D．losing heart at the .signs of difficulties

A．We can find some ways to avoid stress.
B．Stress is always harmful to people.
C．It is easy to change the habit of keeping oneself busy with work.
D．Different people can withstand different amount of stress.

A．they do not know how to enjoy themselves
B．they do not believe that relaxation is important for health
C．they are traveling fast all the time
D．they are becoming busier with their work