从方框中选出适当的句子完成对话。

Tom: Hi! Alice, you look so sad.   1  

Alice: I failed the English exam.

Tom:   2  But you don't need to worry about it all the time.

Alice: I really don't know how to study English well.   3  

Tom:l think you'd better study with a group.

Alice : Oh , that's a good idea.  4  

Tom : Certainly. And we can learn from each other.

Alice : Sounds good. When can I join you?

Tom:   5  

Alice: That's very kind of you.

1._____ 2._____ 3._____ 4._____ 5._____

关于市场组合，下列叙述错误的是( )。

A．它包括所有风险资产

B．它在有效边界上

C．市场组合中所有证券所占比重和它们的市值成正比

D．它是资本市场线和无差异曲线的切点