---Are you free after school?

---Sorry, I’ve planned to treat a friend of mine to dinner___for his help.

A．in trouble

B．in fact

C．in total

D．in return

当项目的全部投资收益率大于贷款利率时，增加负债，自有资金的收益率（）

A.不变

B.增加

C.减少

D.不确定