a.) SELECT Hausmeister from Professor P, Gebaeude G where P.Gebaeude = G.Gebaeude and P.P_Name = "Weikum"; b.) SELECT distinct S.Matrikel_Nr from Fachrichtung F, Student S, Pruefung P where P.Pruefer = F.Studiendekan AND S.Fachrichtung_Nr = F.Fachrichtung_Nr AND S.Matrikel_Nr = P.Matrikel_Nr; c.) selec P.Gebaeude, P.Raum from Professor P, Student S, Pruefung K where S.S_Name = "Hugo Meier" AND K.Matrikel_Nr = S.Matrikel_Nr AND K.Pruefer = P.P_Name and K.Fach = "Betriebssysteme"; d.) SELECT Matrikel_Nr from Student S where Semester > 3 AND NOT EXISTS (SELECT * from Pruefung P where P.Matrikel_Nr = S.Matrikel_Nr); e.) SELECT S.Matrikel_Nr from Student S WHERE NOT EXISTS (SELECT * from Professor PO, Pruefung PU where S.Fachrichtung_Nr != PO.Fachrichtung_Nr and PU.Matrikel_Nr = S.Matrikel_Nr ); f.) SELECT S.Matrikel_Nr from Student S where NOT EXISTS ( SELECT * from Pruefung P where P.Note != 1.0 AND S.Matrikel_Nr = P.Matrikel_Nr); g.) SELECT Matrikel_Nr, AVG(Note) from Pruefung group by Matrikel_Nr; h.) SELECT Matrikel_Nr FROM Pruefung P1 WHERE Note > (SELECT AVG(Note) FROM Pruefung P2 WHERE P1.Fach = P2.Fach); i.) create view Druchschnitt (Fach, DS) AS SELECT P.Fach, AVG(P.Note) GROUPED BY P.Fach; select MAX(DS) from Durchschnitt; j.) select Matrikel_Nr FROM Pruefung P1 WHERE NOT EXISTS (SELECT Matrikel_Nr FROM Pruefung P2 WHERE P1.Note > P2.Note AND P1.Fach = P2.Fach);