Training Guide: Programming in HTML5 with JavaScript and CSS3 Ebook

414 CHAPTER 9 Asynchronous operations

Lesson 2

1. Correct answer: D
   A. Incorrect: There is no updateDom() method.
   B. Incorrect: There is no workerUpdate() method.
   C. Incorrect: There is no dom() method.
   D. Correct: The web worker cannot modify the DOM.


2. Correct answer: D
   A. Incorrect: There is no JavaScript Mutex object.
   B. Incorrect: There is no JavaScript Semaphore object.
   C. Incorrect: There is no JavaScript Closure object.
   D. Correct: The web worker cannot access the same object, and objects passed to
   the web worker from the creator are serialized to produce a copy of the object the
   web worker will access.