题目9A. (CH3)3C·>(CH3)2CH·>CH3CH2·>CH3·B. CH3·>CH3CH2·>(CH3)2CH·>(CH3)3C·C. CH3CH2·>(CH3)2CH·>(CH3)3C·>CH3·D. (CH3)2CH·>(CH3)3C·>CH3CH2·>CH3·