You are given the following source material.
"The store must comply with the working regulations which are as follows. Employees under the age of 16 on the date they joined the company must not work more than 20 hours in any week. All other employees must not work more than 48 hours in any given week, unless they have chosen to opt out of the Working Time Directive regulations. Note the option to opt out is not available to employees under the age of 21." You have created a policy model from the above source material, and have created and used all of the attributes below. Your rules include an entity of "the employee".
Which four are the minimal set of input attributes?