A:C3H10O2
B:C9H8O2
C:C9H10O2
D:C9H12O2
— Whose ____ (knife) are in the desk? —They are Ann’s and Dick’s.
如图所示甲、乙是两种声音的波形图,从图形可知: ____ 图是乐音的波形 ____,图是噪声的波形.
珠穆朗玛峰是世界上最高山峰,海拔约8848米.
读作:____
下列各能源中,属于可再生能源的是( )