题目9.设随机变量X服从参数为1的泊松分布,则 P(X=2)=-|||-A. 1/e-|||-B.2/e-|||-C.1/2e-|||-D. https:/img.cdnjtzy.com/zyb_649a9d9f3a1e543a277582e77a59ed8f.jpg/(e)^2题目解答答案