(1) Which member of each pair of reactions occurs the most rapidly and by what mechanisms? (PLEASE SEE FILE ATTACHMENT).
(2) When (2S, 3S)-3-bromo-2-methoxybutane undergoes an SN2 reation with methoxide ion then the obtained product is not optically active. Why does the 3-bromo-2-methoxybutane have the formula CH3-CH(OCH3)-CHBr-CH3?
(PLEASE SEE FILE ATTACHMENT).