In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Let me give you an 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. Question: When did the operation during which the 704th dropped supplies to allied troops near Nijmegen begin?
The answer to this example can be: from 17 to 25 September 1944
Here is why: The passage describes the 704th's actions during Operation Market Garden, and the answer specifies when the operation happened.

OK. solve this:
Passage: Anderson was born in Edinburgh in 1832. He studied medicine at the University of Edinburgh, graduating with an MD in 1853. While at University he became interested in botany, and earned a gold medal for the best local collection of plants, and assisted in arranging the Indian herbarium. In 1854 he entered the Bengal medical service, and went to Calcutta. Subsequently he went to Delhi, where he was actively engaged during the mutiny, returning to Calcutta in 1858. His health failing, he came home, and, the steamer being detained at Aden for some days, he made an interesting collection of the plants of that region, upon which he based his 'Florula Adenensis,' published in 1860. About this time he returned to India, taking temporary charge of the Calcutta Botanic Garden during the absence of Dr Thomas Thomson, whom he afterwards succeeded as director. His brother, John Anderson was a zoologist.
Link Information: His brother, John Anderson was a zoologist. Question: What age difference was there between Anderson and his brother?
Answer:
Answer: 1