地壳表层有两个主要热能来源：一个是（），另一个是来自地球内部的热流。
A、地壳运动摩擦
B、太阳的辐射
C、大气
D、太空
参考答案：B
It is reported that the United States uses _______ energy as the whole of Europe. [ ]
A. as twice
B. twice much
C. as twice much
D. twice as much
当日申报转回的债券，当日不可以卖出。( )
