函数至少在取a、b、c、d四个参数值时与U形平均成本曲线相一致。
Suppose the long - run total cost function for an industry is given by the cubic equation TC =a+bq+cq2+dq3. Show (using calculus ) that this total cost function is consistent with a U - shaped average cost curve for at least some values of a, b, c, d.
A.城建税应在上海缴纳
B.城建税应在北京缴纳
C.城建税的计算适用7%的税率
D.城建税为0.0325万元
A.2000
B.1.25
C.6.25
D.10000
设随机变量U~U[-2,2],随机变量
试求:(I)X和Y的联合概率分布
(II)D(X+Y)