Sololearn JavaScript course Core Objects answers

Here are all the questions and answers that I hope will help you learn JavaScript course.
Sololearn JavaScript course Overview answers
Sololearn JavaScript course Basic Concepts answers
Sololearn JavaScript course Conditionals and Loops answers
Sololearn JavaScript course Functions answers
Sololearn JavaScript course Objects answers
Sololearn JavaScript course DOM & Events answers
Sololearn JavaScript course ECMAScript 6 answers

37.1 Lesson

Arrays

Question:

JavaScript Arrays
What two keywords do we need to create an array?

Answer:

new
Array

Question:

Accessing an Array
What is the output of this code?

var arr = new Array(3, 6, 8);
document.write(arr[1]);

Answer:

6

Question:

Accessing an Array
What is the result of trying to reference an array member which does not exist?

Answer:

undefined

38.1 Lesson

Other Ways to Create Arrays

Question:

Creating Arrays
Please insert the missing characters to output the third member of the array:

Answer:

document.write(example[2]);

Question:

Creating Arrays
By entering var example = new Array(); we create an empty array which can be filled...

Answer:

anytime later

39.1 Lesson

Array Properties & Methods

Question:

The length Property
Array has the "length" property, because it is:

Answer:

an object

Question:

Combining Arrays
The "concat" method takes two arrays and:

Answer:

combines them in one new array

40.1 Lesson

Associative Arrays

Question:

Associative Arrays
In associative arrays, index numbers are replaced with:

Answer:

strings

Question:

Associative Arrays
In order to use associative arrays, the "associated" name is put in:

Answer:

brackets [ ]

41.1 Lesson

The Math Object

Question:

The Math Object
In the Math Object, which of the following constants does NOT exist?

Answer:

Math.ABC

Question:

Math Object Methods
In the Math Object, which of the following methods is used to calculate the square root?

Answer:

sqrt

Question:

The Math Object
What is the result of the following expression:

Math.sqrt(81);

Answer:

9

42.1 Lesson

The Date Object

Question:

setInterval
Fill in the blanks to call the function "calc()" every 2 seconds:

Answer:

setInterval(calc, 2000);

Question:

The Date Object
What information results from creating a Date Object?

Answer:

The current date and time

Question:

Date Methods
Fill in the blanks to initialize a date object representing the current date and time:

Answer:

var date = new Date();

43.1 Lesson

Module 6 Quiz

Question:

Given the array below, please complete the expression to be alerted with "apple".

Answer:

var fruits = new Array("pear", "orange", "apple", "grapefruit");
alert(fruits[2]);

Question:

What is the result of the following expression?

alert(Math.sqrt(36));

Answer:

6

Question:

Please fill in the blanks to output the current minutes:

Answer:

var date = new Date();
alert(date.getMinutes());

Question:

What is the output of this code?

var arr = new Array("a", "b", "c"); 
alert(arr[1]);

Answer:

b

Question:

Drag and drop from the options below to get alerted with the value of the PI constant.

Answer:

alert(Math.PI);