acquiescent vs difficult

acquiescent

adj
  • willing to acquiesce, accept or agree to something without objection, protest or resistance 

  • resting satisfied or submissive; disposed tacitly to submit 

difficult

adj
  • Hard to manage, uncooperative, troublesome. 

  • Hard, not easy, requiring much effort. 

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