关于声现象,下列说法错误的是( )
A:声音具有能量
B:声音是由物体振动产生的
C:通常情况下,声音在空气中传播得最快
D:声音是一种波
As for my experience last night, I was in a nightclub then and a fight between two young men broke in.____
用简便方法计算.
15.24 ×99+15.24=( )