Consider the AIRLINE relational database schema shown below. Specify the following queries in relational algebra: a. For each flight, list the flight number, the departure airport for the first leg of the flight, and the arrival airport for the last leg of the flight. b. List the flight numbers and weekdays of all flights or flight legs that depart from Houston Intercontinental Airport (airport code 'iah') and arrive in Los Angeles International Airport (airport code 'lax'). c. List all fare information for flight number 'co197'. d. Retrieve the umber of available seats for flight number 'co197' on '2009-10-09'. e. Make up 3 additional queries in English and provide the respective relational algebra commands. Be creative! AIRPORT Airport_code Name City State FLIGHT Flight_number Airline Weekdays FLIGHT_LEG Flight_number Leg number Departure_airport_code Scheduled_departure_time Arrival_airport_code Scheduled_arrival time LEG INSTANCE Flight number Leg_number Date Number_of_available_seats Airplane_id Departure_airport_code Departure_time Arrival_airport_code Arrival time FARE Flight number Fare_code Amount Restrictions AIRPLANE TYPE Airplane_type_name Max_seats Company CAN LAND Airplane_type_name Airport code AIRPLANE Airplane_id Total_number_of_seats Airplane_type SEAT RESERVATION Flight number Leg_number Date Seat number Customer_name Customer phone