In this section, you will hear several passages.
Listen to the passages carefully and then answer the questions that
follow. Questions 11 to 14 are based on the
following passage. At the end of the passage, you will be giv en 20 seconds to
answer the questions. Now, listen to the
passage. Which of the following statements is true according to the passage
A．The longer the sleep is, the more productive the staff is. B．Napping cannot be applied to safety-critical jobs. C．The research was first designed for the astronauts. D．If you sleep more hours awake you are more productive.