宇航员在地球表面以一定初速度竖直上抛一小球，经过时间t小球落回原处；若他在某星球表面以相同的初速度竖直上抛同一小球，需经过时间5t小球落回原处．（取地球表面重力加速度g=10m/s²，空气阻力不计）

图中A；B所代表的铁路枢纽分别是(   )

阅读理解

Sarah: What day is it today?

Mike: It's Monday.

Sarah: What do you have on Mondays?

Mike: We have maths, English, art and science.

Sarah: Do you like science?

Mike: Yes, I like art and English, too. What about you?

Sarah: Me too. Who's your science teacher?

Mike: Mr Zhang.

Sarah: What's he like?

Mike: He's old but very kind and funny. He's tall and thin.

Sarah: What do you often do on the weekend?

Mike: I often listen to music and watch TV. Sometimes I draw pictures.

写出下列词语的反义词。

延误——____         允许——____

植物的根、茎和叶是植物体的生殖器官．