【简答题】请同学们按以下格式书写答案: 1-5 6-10 11-15 16-20 21-25 26-30 31-33 1. There are ___ days in a year. A. three hundreds sixty-five B. three hundreds and sixty-five C. three hundred and sixty-five D. three hundred an...
【单选题】If there are five goods in a barter economy, one needs to know ten prices in order to exchange one good for another. If, however, there are ten goods in a barter economy, then one needs to know ______...