Which ranks these careers that employers are most likely to hire from the least to the greatest?
heating and air conditioning mechanics → solar energy installation managers → biofuels processing tech
heating and air conditioning mechanics → biofuels processing technicians → solar energy installation ma
gas pumping station operators → biofuels processing technicians - solar energy installation managers
gas pumping station operators → solar energy installation managers → biofuels processing technicians =

Employees at a library check out books to patrons. books have an isbn and a name. the library sometimes has multiple copies of the same book. books have one or more authors. a patron is an individual who has an active (non-expired) library card. for each library card, we store the person's first and last names and their address. for each employee, we store their employee id, current salary, first and last name and their address. we also store the employee id of their current manager. each time we check out a book to a patron we need to store the date of the transaction, the employee who checked out the book to the patron, and the library card of the patron. some employees have library cards. if an employee patron turns in a book late, the fine that they pay is a percentage of their salary. some employees are authors who have library cards—they are allowed to check out as many books as they like.