A.各對(duì)比組樣本均數(shù)相等 B.各對(duì)比組總體均數(shù)相等 C.至少有兩個(gè)對(duì)比組總體均數(shù)相等 D.各對(duì)比組總體均數(shù)差別無顯著性 E.各對(duì)比組總體均數(shù)不等
A.大 B.小 C.相等 D.不一定