(1) In this Part, unless the context otherwise requires -

"action" includes omission; and references to the taking of action include references to refraining from action;

"agreement" means any agreement or arrangement, in whatever way and whatever form it is made, and whether it is, or is intended to be, legally enforceable or not;

"business" includes a professional practice and includes any other undertaking which is carried on for gain or reward or which is an undertaking in the course of which goods or services are supplied otherwise than free of charge;

"change of circumstances" includes any discovery that information has been supplied which is false or misleading in a material respect;