A:1:1
B:5:2
C:2:5
D:25:4
孟德尔的豌豆杂交实验非常成功。选择豌豆的优势在于( )
Do you have a baseball bat?
Yes,____ ____ .
Does Ann have a baseball?
No, ____ ____ .
Do Jack and Jim have computers?
Yes, ____ ____ .
Does Chi Yong have a soccer ball?
No,____ ____ .
Do you have a tennis racket?
No,____ ____ .
1972年,经国务院批准,广州春交会向38户美商发出邀请,应邀到会42人,这是中美贸易中断20多年后美商首次到中国参会。与这一事件有直接关系的是( )
请简要回答我国的政党制度及其基本内容是什么?