1) Use a browser's developer tools to view the DOM tree of the document in Fig. 12.4. Look at the document tree of your favorite website. Explore the information these tools give you in the right panel(s) about an element when you click it.
Write a paragraph or two about what you learned doing this exercise.
2) Implement a web page that performs tip calculations. At a minimum, you will need an input element each for the original cost and for the tip rate, and a button to trigger calculations. Use input type=”number” to make input processing a little easier. Use the DOM to access the elements in the web page. Do not use the prompt, alert, or document.writeln methods.