A. shorten the duration of the illness B. the patient buy medicine over the counter C. the patient obtain cheaper prescription drugs D. prevent people from catching colds and the flu 参考答案:A 答案解析:根据第一段的最后一句话“but being able to tell if the cause is a cold or flu may make a difference in how long t
第30题: [单项选择]According to the passage, a barter economy can lead to _________________. A. rapid speed of transaction B. inflation C. misunderstandings D. difficulties for the traders 参考答案:D 答案解析:本题为细节理解题。据第4段最后1句可确定。A和B无原文支持。C与此问题不相关。