352304
Proof : if U is a closed subset of B , then f ^ ( U ) \ cap X and f ^ ( U ) \ cap Y are both closed since the intersection of two closed sets is closed , and f restricted to both X and Y is continuous .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 None