第25题: [单项选择]下列不属于乙烯精馏塔中沸器作用的是()。 A. 使塔的温度分布合理 B. 降低釜温 C. 使塔内汽液相负荷分布均匀 D. 节省热源 参考答案:B
第26题: [单项选择]What does the woman mean A. She has more letters now than before. B. She hasn’t so many letters as before. C. She often hears from her family now. D. She is used to having a lot of letters. 参考答案:B 答案解析:[听力原文] M: Do you often hear from your family W: I used to get a lot of letters, but now they’
第27题: [单项选择]囊肿的声像图特征是 A. 边界回声不定 B. 外形不定 C. 内部无回声 D. 后方回声衰减 E. 侧缘声影不定 参考答案:C 答案解析:囊肿最基本的特征为无回声暗区,边清壁薄。