A CONTRACTUAL AGREEMENT MAY BE EXPRESSED IN WRITING, OR IT MAY BE ORALLY STATED. IN THE ALTERNATIVE, AN IMPLIEDIN FACT CONTRACT: (A) (B) (C) (D) IS CREATED WHEN THE PARTIES MANIFEST THEIR AGREEMENT BY CONDUCT RATHER THAN BY WORDS IS BASICALLY THE SAME THING AS A CONTRACT IMPLIEDBY LAW IS BASICALLY THE SAME THING AS A QUASI-CONTRACT IS BASICALLY THE SAME THING AS AN INVALID CONTRACT