【单选题】The probability density function f ( x ) of a random variable X that is normally distributed is completely determined once the:
A.
mean and median of X are specified.
B.
median and mode of X are specified.
C.
mean and mode of X are specified.
D.
mean and variance of X are specified.
【单选题】Suppose a random variable X can take -1,0,1,2,3, and their corresponding probability is , , , , , then c=
【单选题】下列文学常识有误的一项是______。
A.
被鲁迅誉为“史家之绝唱,无韵之离骚”的《史记》是我国第一部纪传体通史,以写人物传记为主
B.
小说是以塑造人物形象为中心,通过特定的环境和完整的故事情节来反映社会现实生活的一种文体。人物、环境、情节是小说的三要素,其中情节是最重要的要素
C.
词是古代诗歌中的一种文体,是起源于唐朝、兴盛于宋朝的一种配合音乐歌唱的新体诗,又称“长短句”
D.
《故乡》选自鲁迅的小说集《呐喊》,文中的“我”不是作者本人。初中教材中的《从百草园三味书屋》《阿长与(山海经)》《藤野先生》中的“我”都是作者本人
【判断题】A random variable X is called symmetric about zero if for all x onthe real line, 【图片】. Suppose【图片】 is symmetric,then 【图片】.
【判断题】A random variable X is normally distributed with a mean of 150 and a variance of 36. Given that X = 120, its corresponding z -score is 5.0.
【简答题】La réunion 会议 .......................... (se passer 发生/经过) bien.
【简答题】Mes vacances (se passer) _________________bien! C'était vraiment magnifique!
【单选题】摄像机的光学系统一般是由、色温滤色片、基色分光系统等组成的( )。
【单选题】The weighted average of the possible values that a random variable X can assume, where the weights are the probabilities of occurrence of those values, is referred to as the:( )