Visualization is a necessary tool to make sense of information from various sources. The ways to present different data are limited only to your own imagination. a) A height field is a regular array of 2D points h = f(x, y), where h is an altitude above a point (x, y). Height fields are often used to represent terrain data. How would you choose to visualize the height field? Motivate this choice and describe what properties of the data it would express. b) Interactivity is a keyword when dealing with visualization. Mention different types of interaction that would be useful to explore the height field in (a).