Question: Seiersberg is a former municipality in the Austrian state that has what area?

Context paragraphs:
Zerlach: Zerlach is a former municipality in the district of Südoststeiermark in the Austrian state of Styria.  Since the 2015 Styria municipal structural reform, it is part of the municipality Kirchbach-Zerlach.

Spielfeld: Spielfeld (Slovene: "Špilje") is a former municipality in the district of Leibnitz in Austrian state of Styria.  Since the 2015 Styria municipal structural reform, it is part of the municipality Straß in Steiermark.  It was an Austria-Slovenia border crossing checkpoint until December 21 2007, when all immigration and customs checks ended after Slovenia joined the Schengen Area.  The Slovene town opposite Spielfeld is Šentilj.

Styria: Styria (German: Steiermark , ] , Slovene/Croatian: "Štajerska" , Hungarian: "Stájerország" , ) is a state or "Bundesland", located in the southeast of Austria.  In area it is the second largest of the nine Austrian federated states, covering 16401 km2 .  It borders Slovenia and the Austrian states of Upper Austria, Lower Austria, Salzburg, Burgenland, and Carinthia.  The population (as of ) was .  The capital city is Graz which had 276,526 inhabitants at the beginning of 2015.

Seiersberg: Seiersberg is a former municipality in the district of Graz-Umgebung in the Austrian state of Styria.  Since the 2015 Styria municipal structural reform, it is part of the municipality Seiersberg-Pirka.

Sankt Martin am Grimming: Sankt Martin am Grimming is a former municipality in the judicial district of Schladming in the Austrian state of Styria.  In 2015 it merged with the municipality of Mitterberg to form the municipality of Mitterberg-St Martin.

Dirksland: Dirksland ( ) is a town and former municipality on Goeree-Overflakkee Island in the western Netherlands, in the province of South Holland.  The former municipality had a population of about 8,000 in 2007, and covered an area of about 74 km² of which about 19 km² was water.  The former municipality of Dirksland also included the communities of Herkingen, and Melissant.  On January 1, 2013, Dirksland merged with Goedereede, Middelharnis, and Oostflakkee into the new municipality of Goeree-Overflakkee.

Trautmannsdorf in Oststeiermark: Trautmannsdorf in Oststeiermark is a former municipality with 859 inhabitants (1 January 2016) in the district of Südoststeiermark in the Austrian state of Styria.  Since 1 January 2015 Trautmannsdorf is part of a new municipality with Bad Gleichenberg, Bairisch Kölldorf and Merkendorf.  The new municipality is called Bad Gleichenberg.

Sakskøbing: Sakskøbing is a town with a population of 4,519 (1 January 2015) and a former municipality (Danish, "kommune") in Guldborgsund municipality in Region Sjælland on the northeast coast of the island of Lolland in south Denmark.  The former Sakskøbing municipality, including the small island of Vigsø, covered an area of 176 km², and had a total population of 9,299 (2005).  Its last mayor was Kaj Petersen a member of the Social Democrats ("Socialdemokraterne") political party.  The main town and the site of its municipal council is the town of Sakskøbing.  To the north is Tår's Cove ("Tårs Vig") and beyond that Rågø Strait ("Rågø Sund"), the waterway which separates Lolland from Zealand.  A finger of Rågø Strait cuts into the former municipality forming Sakskøbing Fjord and then Sakskøbing River ("Sakskøbing å"), which meanders through the former municipality, as well as through Nykøbing Falster and Nysted until it terminates near the town of Bregninge.

Tyrnau: Tyrnau is a former municipality in the district of Graz-Umgebung in the Austrian state of Styria.  Since the 2015 Styria municipal structural reform, it is part of the municipality Fladnitz an der Teichalm, in the Weiz District.

Pichl-Kainisch: Pichl-Kainisch is a former municipality in the Salzkammergut in the Liezen (district) Austrian state of Styria.  Since the 2015 Styria municipal structural reform, it is part of the municipality Bad Mitterndorf.

Supporting paragraphs: Seiersberg Styria
Answer: 16401 km2