For the example of the simple reservation system used in Section 18.2.1, create specifications for the following operations: (a) CancelSeat (the opposite action to ReserveSeat) (b) AvailableSeats (an...

For the example of the simple reservation system used in Section 18.2.1, create specifications for the following operations: (a) CancelSeat (the opposite action to ReserveSeat) (b) AvailableSeats (an operation which returns the number of unreserved seats)