Which keyword is used to declare a constant variable in JavaScript?
A). const
B). let
C). var
D). constant
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 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 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 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 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 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 data type is used to represent whole numbers in JavaScript?
A). number
B). integer
C). float
D). string
What will be the output of the following code: console.log('Hello ' + 'World');?
A). Hello World
B). Hello + World
C). Hello +World
D). HelloWorld