A group of six inhabitants, comprising Abe, Ben, Cal, Dan, Eric and Frank, was busy in a discussion. A visitor from a nearby city approached them and asked them what type each of them belonged to. Their reply were as follows:
Abe: None of us is a knight. Ben: At least three of us are knights. Cal: At most three of us are knights. Dan: Exactly five of us are knights. Eric: Exactly two of us are knights. Frank: Exactly one of us is a knight.Determine the type of each of the six inhabitants from the aforementioned statements.