人体组织与体液中,下列哪种最能使声衰减程度加重()
A.胆汁
B.血液
C.脂肪
D.胶原纤维
E.钙质
参考答案:E
解析:组织中含钙质越多,声衰减越高。
-Life itself tells us it is necessary to learn to be .One can hardly survive without help from other people in the world.
A.sensitive
B.competitive
C.grateful
D.careful
()是图书馆联盟国际联合体的简写,它标志着图书馆联盟联合体的国际化时代的来临。