Listed below are several hypothetical nucleophilic substitution reactions. None is synthetically useful because the product indicated is not formed at an appreciable rate. In each case provide an explanation for the failure of the reaction to take place as indicated. () + OH- + CH, OH (b) + OH- X + H- () + OH- X HO. (d) + CN- X Br + Br CN (e) NH, + CH,OCH, * CH,NH, + CH,OH (f) NH, + CH,OH, X CH,NH, + H,0