I answered their questions 'to the best of my knowledge'. [=I gave the best answers I could based on what I knew, but I might have answered differently if I had known something else]
No one arrived late 'to my knowledge'. [=I am not aware that anyone arrived late, but it is possible that someone arrived late and I don't know about it]
They went on vacation, 'safe in the knowledge' that the farm would be well cared for while they were away.
(..) Especially if S.H.I.E.L.D. Knows you need it. Well, I didn't know. Hey! The Tesseract has shown me so much. It's more than knowledge. It's truth. I know. What did it show you, Agent Barton? My next target. Tell me what you need. I need a distraction. (..)2012 The Avengers
(..) If your force is as formidable as you claim. You question us? You question him, he who put the sceptre in your hand? Who gave you ancient knowledge and new purpose when you were cast out, defeated? I was a king! The rightful king of Asgard, betrayed. (..)2012 The Avengers