Training Guide: Programming in HTML5 with JavaScript and CSS3 Ebook

554 CHAPTER 14 Making your HTML location-aware

Answers

This section contains the answers to the lesson review questions in this chapter.

Lesson 1

1. Correct answer: C
   A. Incorrect: The watchPosition() method continuously returns the current location.
   B. Incorrect: The watchLocation() method does not exist.
   C. Correct: The getCurrentPosition() method retrieves the current location a single
   time.
   D. Incorrect: The getCurrentLocation() method does not exist.


2. Correct answer: D
   A. Incorrect: The error callback function is a valid paramete.
   B. Incorrect: The position options object is a valid parameter.
   C. Incorrect: The success callback function is a valid parameter.
   D. Correct: The use GPS only parameter is not valid.

Lesson 2

1. Correct answer: A
   A. Correct: The watchPosition() method continuously returns the current location.
   B. Incorrect: The watchLocation() method does not exist.
   C. Incorrect: The getCurrentPosition() method retrieves the current location a single
   time.
   D. Incorrect: The getCurrentLocation() method does not exist.


2. Correct answer: A
   A. Correct: The haversine formula calculates spherical distance.
   B. Incorrect: You use the Pythagorean theorem to calculate the hypotenuse of a right
   triangle.
   C. Incorrect: You use the quadratic formula to solve ax^2 + bx + c = 0 for x.
   D. Incorrect: Hyperbolic functions are analogs of the ordinary trigonometric, or circu-
   lar, functions.