Scrooge observes three people talking about the death of a man, and he asks this Spirit to show him someone who feels emotion at this man's death. Describe what he is shown and its meaning in stave 4.

In stave 4 of Dicken's "A Christmas Carol," Scrooge is shown the home of his employee Bob Cratchit when he asks the Spirit to show him someone who feels emotion at the dead man's passing. Through this experience, Scrooge is privy to a conversation between Bob and his wife, Caroline, concerning their debt. It is not only their debt which concerns them but the thought that it may be transferred to someone more merciless than Mr. Scrooge. This home, even with worry, is in a happier state with the knowledge of Scrooge's passing.
The Spirit shows Scrooge another scene from the Cratchit house, one of deep sadness. The sadness in the Cratchit home comes from the passing of the child Tiny Tim, who was sickly. Scrooge is able to see how deeply this death has affected the family of his employee.
The meaning of these two scenes is that death can have differing effects, such as the death of Scrooge was viewed by the Cratchits, Mrs. Cratchit at least, as the lifting of a burden or a freeing experience, whereas the death of Tiny Tim had the opposite effect. The Spirit shows Scrooge these two scenes to as a means of leading him to the realization that he, Scrooge, will not be missed if he dies continuing to live his life in the manner in which he has become accustomed, but his death will affect the Cratchits in more ways than they realize, yes they feel free from the burden of Scrooge, but at the same time he is their possible means of salvation and the only hope for Tim's survival.
This is the pivotal point in stave 4, Scrooge begins to realize what he needs to do to truly change and how much of an impact he can have, on one family at least.

The Ghost of Christmas Yet To Come shows Scrooge three businessmen talking about someone who's recently passed away. It's clear that they never had much time for the man when he was alive. One of the men says that "Old Scratch (i.e. the devil) has got his own at last, hey?" Scrooge has no idea who the men are talking about, but this was clearly not a well-liked man, whoever he was.
The Ghost then shows Scrooge another group of people happy to see the back of the dead man. He takes old Ebenezer to a seedy pawn shop, a veritable den of iniquity where the criminal classes regularly congregate to fence the various items they've stolen. Inside the shop, a group of unsavory characters are trying to sell the dead man's belongings such as bed curtains, blankets, and a dress shirt. Scrooge is utterly appalled at these thieves and the callous way they refer to the poor man they've just ripped-off. It's then that he requests that the Ghost shows him someone, anyone who feels any emotion at the man's death.
The Ghost responds by taking Scrooge to a house where a young couple do indeed feel great emotion at the old man's passing. But their emotion is one of immense joy and relief, not sorrow. The man and his wife positively rejoice at the news of the man's death. They were heavily in debt to him and so can now sleep soundly in their beds, safe in the knowledge that they've been saved from financial ruin.
No prizes for guessing that the dead man to which everyone has been referring is none other than Ebenezer Scrooge himself. The death of this mean old skinflint, far from being an occasion for sorrow, has been a cause for celebration for so many. This tells you everything you need to know about what kind of a man Scrooge has been, and how much misery he's spread throughout his life.