Javascript Quiz

What is the output of the following code snippet?

• 1

• 2

• undefined 

• ReferenceError

Which of the following comparisons return true in JavaScript?

• 1 and 3

• 1 and 4 

• 2 and 3 

• 2 and 4

What is the value of arr3 after executing the following code snippet?

• [1, 2, 3, 4, 5, 6] 

• [1, 4, 2, 5, 3, 6] 

• [4, 5, 6, 1, 2, 3] 

• [1, 2, 3]

Which of the following statements is true about JavaScript variables?

• Variables must be declared using the 'var' keyword. 

• Variables can be assigned values of any data type. 

• Variables can be redeclared within the same scope using the 'let' keyword. 

• Variables declared using the 'const' keyword can be reassigned a new value.

Which of the following is a valid way to create an empty object in JavaScript?

• var obj = {}; 

• var obj = (); 

• var obj = []; 

• var obj = "";

What is the index of the first element in a JavaScript array?

• 0

• 1

• -1

• NaN

Which of the following is a valid way to access an element in a JavaScript array?

• array(element) 

• array[element] 

• array{element} 

• array.element

What is the correct syntax for creating a JSON object in JavaScript?

• { name: "John", age: 30 } 

• { "name": "John", "age": 30 } 

• [ "name", "John", "age", 30 ] 

• "name": "John", "age": 30

Which of the following is an example of type casting in JavaScript?

• Converting a string to a number using the Number() function

• Converting a number to a string using the String() function.

• Converting a boolean to a number using the Number() function.

• All of the above.

Which of the following loop statements in JavaScript allows you to execute a block of code repeatedly as long as a certain condition is true?

• for loop

• while loop

• do...while loop

• all of the above