劳动行政部门对违反劳动和社会保险法律、法规或者规章的行为的调查，应当自立案之日起（)个工作日

Which of the following is the reason for the differences in clothing？

A．Materials used for clothes differ from country to country.

B．Cotton is the common material for clothing.

C．Man-made materials are invented to make clothes.

D．Most people like silk clothes.

For what reason did the black walnut tree become popular during the colonial period？

A．It was used for gun stocks.

B．It was used by cabinetmakers.

C．It was used as filtering material in gas masks.

D．It provided shade during summer and nut for food.

One reason why the writer was successful in her first business was that

A．she was used to dealing with people.

B．she was open with the staff.

C．the business was already doing well when she started.

D．the staff agreed with all her decisions.

The first reason that the British do not buy snow-ploughs is that ______.

A．spreading salt is good enough

B．old people need more money

C．snow-ploughs are not used often

D．the hospital is more important

Which of the following is the reason for the differences in clothing？ ______ .

A．Materials used for clothes differ from country to country

B．Cotton is the common material for clothing.

C．Man-made materials are invented to make clothes.

D．Most people like silk clothes.

One reason why the writer was successful in her first business was that

A．she was used to dealing with people.

B．she was open with the staff.

C．the business was already doing well when she started.

D．the staff agreed with all her decisions.

Which of the following is the reason for the differences in clothing？ ______ .

A．Materials used for clothes differ from country to country

B．Cotton is the common material for clothing.

C．Man-made materials are invented to make clothes.

D．Most people like silk clothes.

Which of the following is the reason for the differences in clothing？

A．Most people like silk clothes．

B．Man-made materials are invented to make clothes．

C．Cotton is the common material for clothing．

D．Materials used for clothes differ from country to country．

reeks in the eighth century B. C. These coins, which were made of electrum, a natural combination of gold and silver, were irregular in weight and quality. The pure gold and silver coins with related values which appeared during the reign of Croesus (560 -546 B. C. ) provide the first un doubted evidence of standard coinage by state authority. The coins were not perfectly shaped, however, for they were struck with a hand wielded hammer. The trend toward complete mathematical symmetry did not, in fact, begin until the coining press, invented by Leonardo da Vinci in the sixteenth century, was generally used in the middle of the seventeenth century.

One should not assume, however, that only machine made coins are prized for their workmanship. The silver dekadrachm from Syracuse, struck about 413 B. C. , is considered one of the finest Greek coins and is worth more than a thousand dollars today. An artistic masterpiece of a much later period is the silver taler minted in Ratisbon, southern Germany, in 1754.

The value of a coin is not primarily determined by its age, as many people seem to think. Many Greek and Roman coins that were issued in abundance can be purchased for a moderate price. On the other hand, a German coin made of shrapnel during the First World War is very rare and valuable. Among the especially rare United States coins are the 1804 silver dollar, the 1822 five-dollar gold piece, and the 1894 silver dime.

The reason some old Roman coins are NOT costly is that they are ______.

A．available in quantity

B．inferior in workmanship

C．irregular in shape and size

D．made out of inexpensive metal