A:冰受到水的浮力小于冰受到酒精的浮力
B:冰受到水的浮力等于冰的重力大小
C:冰受到酒精的浮力等于冰的重力大小
D:冰受到酒精的浮力大于冰的重力大小
Stop ______ a noise in the library .The students are reading books .
下列哪一项属于学习行为( )