Draw a reaction mechanism using the curved$-$arrow formalism $($include lone pair electrons$)$ for the following base$-$catalyzed transesterification of an ester to give the corresponding alcohol and ester in the presence of sodium $2-$methyl$-1-$propoxide in excess $2-$methyl$-1-$propanol via a nucleophilic acyl substitution reaction. Hint: $3-$steps.

Draw a reasonable mechanism using the curved$-$arrow formalism $($include lone pair electrons$)$ for the following base$-$promoted saponification of an ester with one equivalent of sodium hydroxide in excess water via a nucleophilic acyl substitution reaction followed by an acid workup. Hint: $4-$Steps

Please help!