题目

已知某随机变量X的概率密度函数为P(x)=,则随机变量X落在区间(1,2)内的概率为(     )    A．e2+e      B．      C．e2-e      D． 答案：DRead the passage and fill in the blanks with proper words. (在短文的空格内填入适当的词，使其内容通顺，每空格限填一词，首字母已给) There are different kinds of hotels. But do you know a panda hotel? A panda hotel is going to o1. at the foot of the E’mei Mountain, Sichuan, China. It is the f2. panda-themed (主题的) hotel in the world.There are lots of photos and paintings of those sweet and l3. animals------pandas. And if you are careful enough, you can even f4.them on the teacups in the hotel’s restaurant. The price for o5.room may be from 300 to 500 yuan per night. Now the hotel rooms are a panda lover’s d6.. Do you I want to try it?