Question 3-(2 points) It is important to separate the user interface layer from the other functionality layers for the following reason(s): Technologies used to implement user interfaces are not compatible with those of the other layers In order to increase the level of coupling between the various layers of the system Given that a well-defined API separates the layers, they can evolve independently without affecting each other All of the above None of the above Question 4-(2 points) Which one of the following statements is true about user interface malfunctions? A system should never be commercialized before all malfunctions are eliminated They represent mismatches between what the user wants, needs or expects and what the system provides They are exclusively identified by user interface experts through heuristic evaluations or cognitive walkthroughs They add excitement to the interaction between human and computer as they make the system unpredictable and therefore more interesting None of the above