Given the task definition, example input & output, solve the new input case.
In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.
Example: Passage: The group was occasionally diverted from strategic missions to carry out air support and interdiction missions. It supported Operation Overlord, the invasion of Normandy by attacking transportation targets, including bridges, along with airfields and strong points in France. On D Day, the squadron and the rest of the 446th Group led the first heavy bomber mission of the day. The 446th aided ground forces at Caen and Saint-Lo during July by hitting bridges, gun batteries, and enemy troops. During Operation Market Garden, the attempt to seize a bridgehead across the Rhine in the Netherlands, the 704th dropped supplies to allied troops near Nijmegen. It struck lines of communications during the Battle of the Bulge. During Operation Varsity in March 1945, it supplied ground and airborne troops near Wesel. The squadron flew its last combat mission on 25 April 1945 against Salzburg, Austria. The group had flown 273 missions and had lost 58 aircraft during the war,
. Link Information: Operation Market Garden was a failed World War II military operation fought in the Netherlands from 17 to 25 September 1944. Answer: from 17 to 25 September 1944
Output: When did the operation during which the 704th dropped supplies to allied troops near Nijmegen begin?
The passage describes the 704th's actions during Operation Market Garden, and the answer specifies when the operation happened.

New input case for you: Passage: Halleck's plan, finalized in January 1864, called for Banks to take 20,000 troops up from New Orleans to Alexandria, including the 47th Pennsylvania Infantry, the only regiment from the Keystone State to fight in this campaign, on a route up the Bayou Teche (in Louisiana, the term bayou is used to refer to a slow moving river or stream), where they would be met by 15,000 troops sent down from Major General William T. Sherman's forces in Vicksburg, Mississippi, and under the command of Brigadier General A.J. Smith. Smith's forces were available to Banks only until the end of April, when they would be sent back east where they were needed for other Union military actions. Banks would command this combined force of 35,000, which would be supported in its march up the Red River towards Shreveport by Union Navy Rear Admiral David Dixon Porter's fleet of gunboats. At the same time, 7,000 Union troops from the Department of Arkansas under the command of Major General Frederick Steele would be sent south from Arkansas to rendezvous with Banks in his attack on Shreveport, and to serve as the garrison for that city after its capture.
Link Information: He married Ellen Ewing Sherman and together they raised eight children. Answer: 1
Output:
How many times was the person who sent 15,000 troops married?