Since you are in the preliminary stages of your project, you estimate that your project will most probably last 1 year-however, optimistic scenario is that it will get over within 6 months and pessimistic scenario is 18 months. This kind of estimate is also called （）.

A．definitive

B．capital cost

C．order of magnitude

D．feasibility

关于概率分布，下列选项中说法正确的有（）

A.概率分布越集中，实际可能的结果就越会接近预期收益

B.概率分布越分散，投资风险程度越大

C.非连续式概率分布和连续式概率分布是概率分布的两种类型

D.概率分布越集中，则概率分布中的峰度越高

E.概率分布越集中，则概率分布中的峰度越低