—— 请按键盘 空白键 开始游戏 ——

当且仅当所有投资者都持有均值-方差有效的投资组合时,市场组合才是有效的。
You can't just sit there and wait for people to give you that golden dream. You've got to get out there and make it happen for yourself.
Positive psychology is not just about feeling good, it's about the good life.
农业的成功来自于理解自然,而不是与之对抗。
我不是为了生活而唱歌,我是为了唱歌而生活。