SN$1+$ E$1$ Mechanisms. Using correct mechanistic arrows, provide the step$$by$$step mechanism that

demonstrates how the following reactions proceed to afford both substitution and elimination products via SN$1$

and E$1.$ You do not need to show stereochemistry while providing the mechanism, but show correct

stereochemistry in the final product$($s$).$ If there is more than one product feel free to write $+$E or $+$D as

appropriate $($or just write your products$).$