第24题: [单项选择]Questions 32 to 35 are based on the passage you have just heard.A. A basket. B. A cup C. A egg. D. An oven. 参考答案:B 答案解析:[解析] 32-35 Did you know that there’s a kind of bird that can sew This called the tailor bird
第29题: [单项选择]百分浓度的定义是() A. 每100份溶液中所含溶质的份数 B. 每100g溶液中所含溶质的克数 C. 每100ml溶液中所含溶质的毫升数 D. 每100ml溶液中所含溶质的克数 E. 溶质的份数与溶液的份数之比 参考答案:A 答案解析:百分浓度标准定义是每100份溶液中所含溶质的份数,用符号(%)表示,其包括重量一重量(g/g)即每100g溶液中所含溶质的克数,重量-体积(g/ml)即100ml溶液中所含溶质的克数,体积-体积百分浓