问题
选择题
| — When is your birthday, John? — It's _____. |
A. March 21st B. 21st C. March |
答案
答案：A
搜题请搜索小程序“爱下问搜题”
| — When is your birthday, John? — It's _____. |
A. March 21st B. 21st C. March |
答案：A
可有效地治疗肝癌。该同位素原子核内中子数与质子数之差为