【单选题】我国专业化营销调研公司在什么时间相继成立?
【单选题】The existence of external economies of scale _______.
A.
tends to result in large profits for each firm.
B.
may be associated with a perfectly competitive industry.
C.
cannot be associated with a perfectly competitive industry.
D.
tends to result in one huge monopoly.
【单选题】External economies of scale ( )
A.
may be associated with a perfectly competitive industry.
B.
cannot be associated with a perfectly competitive industry.
C.
tends to result in one huge monopoly.
D.
tends to result in large profits for each firm.
【单选题】The existence of external economies of scale
A.
focuses more on individual firms than the industry as a whole.
B.
tends to result in one huge monopoly.
C.
tends to result in large profits for each firm.
D.
cannot be associated with a perfectly competitive industry.
E.
may be associated with a perfectly competitive industry.
【简答题】外部规模经济(external economies of scale)
【简答题】设微分方程通解为y=C 1 +lnC 2 x,试讨论怎样给定初始条件,可得唯一特解,以及特解的定义域.