Which data type is used to represent whole numbers in JavaScript?
A). number
B). integer
C). float
D). string
What is the purpose of the NaN (Not a Number) value in JavaScript?
A). To represent a number that is not a valid JavaScript number
B). To represent a zero value
C). To represent an infinite value
D). To represent an empty string
Which keyword is used to declare a constant variable in JavaScript?
A). const
B). let
C). var
D). constant
What happens if you declare a variable without initializing it in JavaScript?
A). It will throw a syntax error
B). It will assign the variable a value of undefined
C). It will automatically assign a value to the variable
D). It will assign the variable a value of null
What is the scope of a variable declared using the let keyword in JavaScript?
A). Block scope
B). Function scope
C). Global scope
D). Local scope
Which method is used to convert a string to a number in JavaScript?
A). toString()
B). parseInt()
C). parseFloat()
D). toNumber()
Which statement correctly assigns the value true to a boolean variable isLogged in JavaScript?
A). let isLogged = 'true';
B). let isLogged = true;
C). let isLogged = 1;
D). let isLogged = 0;
What is the purpose of using the === operator in JavaScript?
A). Strict equality comparison
B). Loose equality comparison
C). Assignment operator
D). Addition operator
What is the value of x after the following code executes: let x = 5; x *= 2; x /= 3;?
A). 04-Oct
B). 6666666666667
C). 5
D). undefined
Which of the following is NOT a valid variable name in JavaScript?
A). _myVariable
B). 2ndVariable
C). $myVariable
D). my-Variable