A fast food employee started on a Monday at $9$am and took $12\mathrm{.}5$ minutes to prepare each sandwich in the first hour $(9$am $-10$am$).$ Each hour, the employee was able to get faster at the learning curve rate of $80\%.$ How long will it take the employee to make a sandwich the following Monday between $9$am and $10$am$?$ Assume that the employee works $40$ hours a week.

Hint: The following Monday $9$am $-10$am will be $41$st hour of employment.