• 2022-07-27
    设X~N(3,4),则下列式子一定成立的是
    A: [img=171x25]1803278ac20bca6.png[/img]
    B: [img=171x25]1803278acb1251d.png[/img]
    C: [img=203x29]1803278ad93a645.png[/img]
    D: [img=171x25]1803278ae2318d3.png[/img]