Which variable declaration is appropriate if you want a variable to hold a constant value throughout the program execution?

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 of the following is NOT a valid variable name in JavaScript?

A). _myVariable

B). 2ndVariable

C). $myVariable

D). my-Variable

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

What will be the output of the following code: console.log(parseInt('10.5'));?

A). 10

B). 5

C). '10.5'

D). NaN (Not a Number)

What will be the output of the following code: console.log('Hello ' + 'World');?

A). Hello World

B). Hello + World

C). Hello +World

D). HelloWorld

What will be the value of x after the following code executes: let x = '5' + 5;?

A). '55'

B). 10

C). 5

D). '10'

Which method is used to convert a string to a number in JavaScript?

A). toString()

B). parseInt()

C). parseFloat()

D). toNumber()

What is the keyword used to declare variables in JavaScript?

A). let

B). variable

C). var

D). const

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 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