In this section you will hear everything ONCE ONLY.
Listen carefully and then answer the questions that follow. Mark the correct
answer to each question on your ANSWER
SHEET. Questions 6 to 8 are based on
the following news. At the end of the news item, you will be given 10 seconds to
answer each question. Now listen to the news. According to the news, what caused the growth of the US economy about 200 years ago
A．The new technology used to build roads. B．The ability to transport goods over land. C．The trade in grain and cotton. D．The linking of smaller local roads into one long road.