Final answer:
The characters he might call are his next door neighbor, a resident three floors up, someone from across the street, or his new postal delivery person, reflecting themes of proximity and social networks.
Step-by-step explanation:
The student's question appears to be related to a piece of literature where a character is given three telephone numbers. The individuals he was potentially going to call could be his next door neighbor, someone who lives three floors up in the apartment building, someone from across the street, or his new postal delivery person. Without additional context, it is difficult to discern who exactly the people associated with these numbers are within the narrative.
Nonetheless, these options reflect the connections and relationships one might have within their immediate community, emphasizing themes of proximity and social networks in the literature. The mention of the telephone wire's speed and its association with rumor signifies the quick spread of news and the power of communication in society.