A.±2.58s B.±1.96s C. D. E.
A.變量值都是負(fù)數(shù) B.變量值負(fù)的比正的多 C.計算有錯 D.變量值多數(shù)為0 E.變量值一個比一個小
A.95% B.45% C.97.5% D.47.5% E.48.8%