What will be the value of x after the following code executes: let x = 10; x += 5;?

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

A). _myVariable

B). 2ndVariable

C). $myVariable

D). my-Variable

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

A). let

B). var

C). const

D). constant

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 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(typeof 'Hello');?

A). string

B). number

C). undefined

D). boolean

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;

Which symbol is used for string concatenation in JavaScript?

A). +

B). -

C). *

D). /

Which keyword is used to declare a constant variable in JavaScript?

A). const

B). let

C). var

D). constant

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

A). toString()

B). parseInt()

C). parseFloat()

D). toNumber()

Which data type is used to represent whole numbers in JavaScript?

A). number

B). integer

C). float

D). string