To express the Projection operator it, you can use PI To express the Selection operator o, you can use SIGMA To express the Natural Join operator , you can use JOIN To express the Not Equal comparison operator #, you can use ! name Airport airportid city CDG Charles de Gaulle Paris DXB Dubai International Dubai JFK John F Kennedy International New York LGA LaGuardia New York MIA Miami International Miami SFO San Francisco International San Francisco state NULL NULL NY country FRA UAE USA FL CA USA USA USA Carrier name carrieri AF DL Air France Delta Air Lines Emirates Airline US Airways fleetSize employees revenue 225 84,602 15,414 855 80,000 39,639 239 84,153 18,300 338 31,467 13,050 EK US Flight carrieriD flightNo date time airportID destination distance DL 426 10/16/2017 7:00 AM JFK SFO 2,586 DL 426 10/17/2017 7:00 AM JFK SFO 2,586 DL 479 10/16/2017 7:25 PM JFK SFO 2,586 EK 721 10/17/2017 11:25 AM CDG DXB 3,259 US 783 10/17/2017 3:20 AM DXB JFK 6,843 DU 1472 10/17/2017 7:30 AM LGA MIA 1,099 AF 3577 10/17/2017 5:45 PM JFK CDG 3,629 US 3577 10/17/2017 9:40 AM LGA SFO 2.576 AF 3634 10/16/2017 1:20 PM CDG MIA 4,580 Formulate the following queries in the relational algebra: Display the number of airports. 2 points Your answer Display the number of flights with distances longer than 3,000 miles. 3 points Your answer Display the number and the average revenue of all carriers. 3 points Your answer Display the number and the total distance of flights leaving from JFK. 3 points Your answer 3 points Display the minimum, the average, and the maximum distances of the flights that are scheduled on October 17th, 2017 Your answer Display the number of airports in each country. 3 points Your answer Display the number and the average distance of flights for each carrierID. 3 points Your