Define two W3C accessibility guidelines using examples. Jakob Nielsen published 10 usability heuristics for user interface design. Can these heuristics be used for Web interfaces? Explain using examples. A well-known user interface design guideline is stated in two different guideline sets, “Visibility of system status – Nielsen” and “Offer informative feedback – Shneiderman”. What can a designer do to follow this guideline for a software application? Explain using examples.