A:卵黄膜、卵黄、胚盘
B:卵壳膜、卵白、卵黄
C:卵壳、卵壳膜、卵白、卵黄
D:整个鸡卵
最薄的金箔的厚度为0.000000091m,这个数量用科学记数法可表示为( )
The two cities have reached an _________ to develop science and technology.