第21题: [单项选择]Questions 11 to 18 are based on the conversation you have just heard. A. She doesn’t follow the teacher. B. She has been given too much work. C. She has no interest at the beginning. D. She isn’t used to English teaching. 参考答案:D 答案解析:[听力原文] W: I’m not used to heavy reading load, so many seminars and so many papers to write. M:
第28题: [单项选择]热值范围在34.8~36MJ/Nm3城市燃气是______。 A. 液化石油气 B. 天然气 C. 生物气 D. 人工煤气 参考答案:B 答案解析:[解析] 本题考核的是城市燃气系统不同燃气种类的热值范围。燃气按来源分类可分为如下四种:(1)天然气热值范围在34.8~36MJ/Nm3。(2)人工燃气热值范围在3.8~20.9
第31题: [单项选择]具有激素性质的维生素是() A. 维生素A B. 维生素C C. 维生素E D. 维生素K E. 维生素D3 参考答案:E 答案解析:由于维生素D3是在由贮存于皮下的胆固醇的衍生物(7-脱氢胆固醇),在紫外光照射下转变而成的,但要运往靶器官才能发挥生理作用,故认为维生素D3实质上是敖素。