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: Steve Rogers:  The next wave 's gon na hit any minute . What have you got , Stark ?
Tony Stark: Well , nothing great . Maybe a way to blow up the city . That 'll keep it from impacting the surface if you guys can get clear .
Steve Rogers: I asked for a solution , not an escape plan .
Tony Stark: Impact radius is getting bigger every second . We 're going to have to make a choice .
Natasha Romanoff: Cap , these people are going nowhere . If Stark finds a way to blow this rock ...
Steve Rogers: Not ' til everyone 's safe .
Natasha Romanoff: Everyone up here versus everyone down there ? There 's no math there .
Steve Rogers: I 'm not leaving this rock with one civilian on it .
Natasha Romanoff: I did n't say we should leave .
Natasha Romanoff: There 's worse ways to go . Where else am I gon na get a view like this ?
Nick Fury: Glad you like the view , Romanoff . It 's about to get better .
Nick Fury: Nice , right ? I pulled her out of mothballs with a couple of old friends . She 's dusty , but she 'll do .
Steve Rogers: Fury , you son of a bitch .
Nick Fury: Oooh ! You kiss your mother with that mouth ?
Maria Hill: Altitude is _ eighteen _ thousand and climbing .
Specialist Cameron Klein: Lifeboats secure to deploy . Disengage in three , two ... take 'em out .
Pietro Maximoff: This is SHIELD ?
Steve Rogers: This is what SHIELD 's supposed to be .
Pietro Maximoff: This is not so bad .
Steve Rogers: Let 's load 'em up .

Altitude