Definition: In this task, you will use your knowledge about language (and common sense) to determine what element the marked number refers to. The numbers are marked with two underlines around them, like: _ number _. Your answer should be chosen from the given text, and should not contain other words.
Input: Kade:  Mr. Chambers is lying , he killed the lady .
Billy Ruckman: What 'd you say ?
Kade: Mr. Chambers is lying , he killed the lady .
Billy Ruckman: You heard him , that was his student , and they were rehearsing the scene from one of his operas .
Kade: They were n't pretending , because she never got back up after he pushed her down .
Billy Ruckman: She never got up ? Wait , how do you know this ?
Kade: I saw them .
Billy Ruckman: When ?
Kade: When you went to the bathroom .
Billy Ruckman: You saw what I saw ? Why did n't you tell me sooner ?
Kade: Every time I tried to tell you , you always tell me to shut up .
Billy Ruckman: I knew he was lying , I could feel it . Okay , here 's what we 're going to do : he 's going to try and get rid of that body tonight , I just know it . We 're going to have to take turns watching his house . Okay , it 's 11 o ' clock , that means we 've got 7 hours until it 's light ... Are you tired ?
Kade: No .
Billy Ruckman: Okay , you take the first three hours , and I 'll take the last _ four _ .

hours