Q1) The first story was set at at the stairwell in the evening. The second story was set in Watson's house in the morning. The third story was set in the neighborhood of a town.

Q2)The first story was set in the modern day. The second story was set in 1883, early April in the morning. The third story was set in the early 19th century England.

Q3) The setting of the first story tells us that the story was going to be moody and sad. The setting of the second story tells us that the story was going to be suspicious and mysterious. The setting of the third story gives us a very amiable feeling and and gives us warm and loving effect.