Why does it say the IRR rule can be misleading when decide the mutually exclusive projects?

Why does it say the IRR rule can be misleading when decide the mutually exclusive projects? Why does the author say it's impossible to sum up the British people with a few simple phrases What does the fox say?能去掉does吗额,What does the fox say?的does可以去掉吗?Why? Why does the Earth move?Why does it rotate around the Sun?Why does it spin anticlockwise? what does it say What does it say? what does it say? Why does it say the IRR rule has pitfall when dealing with the multiple rates of return?求答案~~~求着到题目的英语答案。。。 1.When I try to understand_____ that prevents so many Americans from being as happy as one might expect,it seems to me that there are two causes.A.why it does B.what it does C.what it is D.why it is2.There's a flower show in the park.what do you say “why” what does it means? Why does the child want to have a bus ride?的中文还有一些：Where does the bus stop?Who is coming when the bus stops?What does the woman say?What day is it today?where are Mingming and Dongdong?what are the boys doing?What are the girls doing? What does the r_____ say about the movie?It says that the film is very imaginative. What does the teacher say? What does the fox say? why does the bird fly Why does Psyche say,Your beauty is like a shell,in which you,the real you,have to live? Why i can not say it. It was hard to say why the man deserved such shabby treatment.