7. Which of the following statements is/are incorrect ?
(a) Mapping the co-ordinates of the points and lines that form the picture into the appropriate co-ordinates on the device or workstation is known as viewing transformation.
(b) The right handed cartesian co-ordinates system in whose coordinates we describe the picture is known as world coordinate system.
(c) The co-ordinate system that corresponds to the device or workstation where the image is to be displayed is known as physical device co-ordinate system.
(d) Left-handed co-ordinate system in which the display area of the virtual display device corresponds to the unit(|x|) square whose lower left handed corner is at origin of the co-ordinate system, is known as normalized device co-ordinate system.