number - Shelosha?

Who knows three?

Please cite/link your sources, if possible. In about a day, I will:

• 
  

  Upvote all interesting answers.

  
  


• 
  

  Accept the best answer.

  
  


• 
  
  

  Go on to the next number.

  
  

Answer

1. 
   

   The number of years required to establish a chazaka on a piece of property.

   
   


2. 
   

   Men (or women) required for a zimmun.

   
   
   


3. 
   

   Hours waited between meat and dairy in the German tradition.

   
   


4. 
   

   Ostensibly, the number of people in front of whom lashon hara can be told and it becomes repeatable (though the Chafetz Chaim points out that it is not really applicable).

   
   


5. 
   

   Number of times one has to ask forgiveness from a friend for wrongdoing.