Pass the WGU Courses and Certificates Web-Development-Applications Questions and answers with ExamsMirror

To invoke the CSS provided, an ID selector is used. In CSS, the ID selector is used to style the element with the specific id attribute.

CSS ID Selector: The syntax for the ID selector is #id, where id is the id attribute value of the HTML element.

Usage Example:

#black {

color: black;

}

This CSS rule will apply the color: black; style to the element with id="black".

Example in HTML:

References:

MDN Web Docs on ID Selectors

W3C CSS Specification on Selectors

If the type attribute is omitted from an <input> element, it defaults to text.

HTML Input Default Type:

Default Type: The default value for the type attribute in an <input> element is text.

Example:

Given the HTML:

<input>

This will render as a text input field.

References:

MDN Web Docs - <input>

W3Schools - HTML Input Types

The watchPosition method in the Geolocation API is used to get periodic updates about the geographic location of a user.

watchPosition Method: This method calls the provided callback function with the user's current position as the device's location changes.

Usage Example:

navigator.geolocation.watchPosition(function(position) {

console.log("Latitude: " + position.coords.latitude + ", Longitude: " + position.coords.longitude);

});

In this example, the watchPosition method continuously logs the user's latitude and longitude to the console as the position changes.

References:

MDN Web Docs on watchPosition

W3C Geolocation API Specification

To ensure that a message appears if the user’s browser does not support the audio files on a web page, the developer should use the <audio> element correctly. The <audio> element supports fallback content, which is displayed if the browser does not support the specified audio formats.

Correct Usage:

Fallback Content: Place the message as fallback content inside the <audio> element. Browsers that do not support the audio format will display this message.

Example:

<audio>

No mpeg support.

</audio>

Explanation of Options:

Option A: Incorrect. The alt attribute is not valid for the element.

Option B: Incorrect. The alt attribute is not valid for the <audio> element.

Option C: Incorrect. The alt attribute is used incorrectly in the <audio> element.

Option D: Correct. The message "No mpeg support." is placed correctly as fallback content inside the <audio> element.

References:

W3C HTML5 Specification - The audio element

MDN Web Docs - <audio>

Using the fallback content inside the <audio> element ensures that users with unsupported browsers receive a meaningful message, improving the overall user experience.

The given code snippet demonstrates how JavaScript can manipulate the DOM to change the style of an element.

Code Analysis:

Given the HTML:

<h1 id="id1">Blog Title</h1>

Click Here

When the button is clicked, the JavaScript code within the onclick attribute changes the color of the h1 element to red.

Explanation:

Option A: An event handler tracking keyboard strokes is incorrect because the event handler is tracking a mouse click, not keyboard strokes.

Option B: JavaScript is using the DOM to make a style change is correct because the onclick attribute contains JavaScript code that modifies the style of the h1 element.

Option C: In-line CSS is styling the <h1> tag is incorrect because the style change is done via JavaScript, not inline CSS.

References:

MDN Web Docs - Document.getElementById()

W3Schools - JavaScript HTML DOM

JavaScript is often described as an object-based language, meaning it is centered around objects. While it supports object-oriented programming (OOP) concepts, it is more accurate to describe it as object-based due to its prototypal inheritance model rather than classical inheritance.

Object-Based: JavaScript is built around objects and supports the creation and manipulation of objects.

Object-Oriented Features: JavaScript supports OOP principles like encapsulation, inheritance, and polymorphism, but through prototype chains rather than class-based inheritance.

Functional and Event-Driven: JavaScript supports functional programming and is often used in an event-driven manner, particularly in the context of web browsers.

References:

MDN Web Docs on JavaScript Object Model

W3C JavaScript Overview

In JavaScript, the name of a function is defined after the function keyword and before the parentheses that enclose its parameters.

Function Name: The function name is the identifier used to call the function. It is defined immediately after the function keyword.

Usage Example:

function square(number) {

return number * number;

}

In this example, the name of the function is square.

References:

MDN Web Docs on Functions

ECMAScript Language Specification

To specify a cache manifest file for an HTML document, the manifest attribute must be set in the <html> element. This attribute tells the browser to cache the files listed in the manifest for offline use.

Cache Manifest:

Purpose: Specifies resources that should be cached by the browser.

Attribute: manifest is used in the <html> tag to link the cache manifest file.

Example:

Given the manifest file application.appcache:

CACHE MANIFEST

CACHE:

default.html

stylesheet.css

functions.js

logo.jpg

HTML with the manifest attribute:

<html manifest="application.appcache">

</html>

References:

MDN Web Docs - Offline Web applications

W3C HTML5 Specification - manifest attribute

The CSS property vertical-align: baseline aligns the baseline of the element with the baseline of its parent. For inline elements like images, the baseline alignment means that the bottom of the image aligns with the bottom of the text.

CSS vertical-align Property:

Baseline Alignment: Aligns the baseline of the element with the baseline of its parent.

Example:

Hello World

Analysis:

The element with vertical-align: baseline will align its bottom with the bottom of the surrounding text "Hello World".

References:

MDN Web Docs - vertical-align

W3C CSS Inline Layout Module Level 3

The onpopstate event is triggered in the window object when the active history entry changes, such as when the user navigates to a different page using the back or forward buttons in the browser.

History API and onpopstate:

Event: window.onpopstate

Description: This event is fired when the user navigates to a session history entry, i.e., when moving backwards or forwards in the browser history.

Example:

window.onpopstate = function(event) {

console.log("location: " + document.location + ", state: " + JSON.stringify(event.state));

};

Other Options:

A. Window, location: location is an object containing information about the current URL.

C. Window, name: name is a property to set or get the name of a window.

D. Window, open: open is a method to open a new browser window or tab.

References:

MDN Web Docs - window.onpopstate

W3Schools - JavaScript History API