string up vs whack

string up

verb
  • To kill (a person) by hanging, especially to lynch. 

  • To concatenate; to link in a line. 

  • To suspend by means of rope, cord or similar material. 

whack

verb
  • To kill, bump off. 

  • To surpass; to better. 

  • To beat convincingly; to thrash. 

  • To hit, slap or strike. 

  • To share or parcel out (often with up). 

noun
  • An attempt, a chance, a turn, a go, originally an attempt to beat someone or something. 

  • The sound of a heavy strike. 

  • The strike itself. 

  • The backslash, ⟨ \ ⟩. 

  • The stroke itself, regardless of its successful impact. 

How often have the words string up and whack occurred in a corpus of books? (source: Google Ngram Viewer )