In this task, you're given a question, along with three passages, 1, 2, and 3. Your job is to determine which passage can be used to answer the question by searching for further information using terms from the passage. Indicate your choice as 1, 2, or 3.

Question: How long after the Battle of Princeton did the war during which Fort Mercer was built end? Passage 1:The Calgary Flames selected him in the eighth round, 182nd overall at the 1981 NHL Entry Draft, and he began his professional career in 198384 with a 30-point season for the Colorado Flames of the Central Hockey League (CHL). He then spent the majority of three seasons in the American Hockey League (AHL) with the Moncton Golden Flames. He was named to the AHL second All-Star Team in 198485, and served as captain of the Golden Flames in 198586. DeGray appeared in one NHL game that season, making his NHL debut with Calgary on March 6, 1986, against the New York Rangers. He played a part-time role in Calgary in 198687; in 27 games with the Flames, DeGray scored six goals and seven assists.
Passage 2:Musicki was stationed in Slavonski Brod at the time of the Axis invasion of Yugoslavia in April 1941 and served as the Royal Yugoslav Army commander responsible for the railroad between Belgrade and Zagreb in the rank of colonel. He demonstrated his support for the Germans by helping their forces during the invasion. Yugoslavia was quickly conquered by the Axis powers and Musicki remained in Slavonski Brod for several months after the conquest. He attempted to join the Ustase Militia there, but was rejected. He went to Belgrade in mid-August, where he was received by Zbor leader Dimitrije Ljotic. On 6 October, Milan Nedic, the Prime Minister of the Axis-installed puppet Government of National Salvation, appointed Musicki to lead the Serbian Volunteer Command (, SDK). Musicki was involved in executing Serb civilians in the town of Cacak in December 1941. He and Milan Acimovic contacted Chetnik leader Draza Mihailovic on 5 December, possibly in an effort to warn him in advance of the assault the Germans had planned, codenamed Operation Mihailovic. This action prompted the Germans to question Musicki's loyalty. He was removed from command at the end of 1941 and imprisoned by the Germans, but was later freed at Nedic's intervention.
Passage 3:Fort Mercer was a fort on the Delaware River in New Jersey constructed by the Continental Army during the American Revolutionary War. Built by Polish engineer Thaddeus Kosciuszko under the command of George Washington, Fort Mercer was built in 1777 to block the approach to Philadelphia, Pennsylvania in concert with Fort Mifflin on the Pennsylvania side. Fort Mercer was located in an area called Red Bank, in what is now the borough of National Park, Gloucester County, New Jersey. The fort was named in honor of Brigadier General Hugh Mercer who had died earlier that year at the Battle of Princeton. The fort's site is now part of Red Bank Battlefield Historical Park, which includes a monument and museum. Several cannons attributed to British warships lost supporting the attack on the fort, and others found buried at the fort itself, are in the park.
3