用弹簧测力计测出一个物体重为8N，然后将该物体浸没在水中，这时弹簧测力计的示数变为6N，则该物体在水中受到的浮力是（　　）

下列物质中，暗反应阶段所必需的是（  ）

下列化学反应中不属于化合反应的是（   ）

请根据老师与同学们的对话，为衣物找到主人。
A: Is this your cap?
B: No, it's Mary's.
A: Is this your skirt, May?
B: No, it isn't. It's Lily's.
A: Is this your skirt, Lily?
C: Yes, it is.
A: Are these your gloves?
C: No, they aren't. They are Tom's.
A: Are these your shorts, Li Hai?
D: Yes, they are.
A: Whose scarf is this?
D: It's May's.
⑴Mary  ____                A.
⑵Lily  ____                 B.
⑶Tom  ____              C.
⑷Li Hai  ____               D.
⑸May  ____                E.

下列有关能源叙述不正确的是