Realtional Calculus Question:

Question:

Hi There, this question above has had me stuck for the past couple of hours. It is suppose to be answered with relational calculus. Any help is appreciated!

Consider the following relational schema for a travel agency CLIENT(ClientID, Client Name, Client City, ClientDiscountPct) stores the identifier, name, and residence city for each client as well as the percentage discount he/she qualifies for each booking TRAVELAGENTOAID, TAName, TACity, TACommissionPct) stores the identifier and base city for each travel agent as well as the percentage commission rate on each booking. FLIGHT (Flight Num, FromCity, ToCity, FromAirport, ToAirport) stores for each flight the flight number, the source and destination cities and air- ports. DAILYFLIGHTOFlight Num, Date, Seats, Price) stores for each day's flights the flight number, date, number of seats; and nominal price per seat. FlightNum is a foreign key referring to FLIGHT. BOOKING (Booking ID, Client ID, TAID, Flight Num, Date, NumSeats, Cost stores the identifier of each booking, the identifiers of the involved client, travel agent and flight, the number of seats booked, and the final cost to the client (this cost is equal to the price per seat times the number of seats less the client's dis- count). Client ID, TAID, and (FlightNum, Date) are foreign keys referring to CLIENT TRAVELAGENT, and DAILYFLIGHT respectively