A:x=2
B:锗原子的电子数为32
C:人体中锗是常量元素
D:锗原子的中子数为41
阅读短文,选择正确的答案。
I have got a toy bear. It's white. It has a small red hat and a black coat. Its name is Winnie. It's very lovely. I like to play with Winnie.
①月食;②太阳东升西落;③麦哲伦环球航行;④人卫星获取的太空影像;⑤四季变化