非均质性液体(介质)如尿液中混有血液和沉淀,囊肿合并出血或感染时,液体内回声
A.液体内回声不变
B.液体内回声衰减
C.液体内回声增强
D.无回声
E.低回声
参考答案:C
Deeply his unhappy childhood, the boy’s seemed quite odd and strange.
A.relating to; characters
B.associated with; personality
C.linked by; virtues
D.connecting to; morality
什么是天然气绝对湿度?