Q
What is the output of const x = 10; x = 20;?

Answer & Solution

Answer: Option C
Solution:
Assigning a new value to a constant variable will throw an error because const variables are read-only.
Related Questions on Average

What keyword is used to declare a block-scoped variable in ES6?

A). var

B). let

C). const

D). function

What does the for...of loop iterate over?

A). Object properties

B). Object values

C). Array indices

D). Iterable objects

How do you export a function in ES6 modules?

A). export function myFunc() {}

B). module.exports = myFunc;

C). exports.myFunc = function() {}

D). export myFunc = function() {}

What is the syntax for an arrow function in ES6?

A). function(a, b) { return a + b; }

B). (a, b) => { return a + b; }

C). (a, b) => a + b

D). Both B and C

How do you declare a constant variable in ES6?

A). const

B). let

C). var

D). function

How do you check if a value is an array in ES6?

A). Array.isArray(value)

B). value.isArray()

C). value instanceof Array

D). typeof value === 'array'

How do you interpolate variables in a string using template literals?

A). Hello, + name + '!'

B). Hello, ${name}!

C). 'Hello, ' + name + '!'

D). Both A and B

What is the output of typeof Symbol('description')?

A). 'string'

B). 'object'

C). 'symbol'

D). 'undefined'

What is the output of [...'hello']?

A). ['hello']

B). ['h', 'e', 'l', 'l', 'o']

C). [104, 101, 108, 108, 111]

D). ['h', 'e', 'll', 'o']

What is the correct syntax to create a class in ES6?

A). class MyClass {}

B). class = MyClass {}

C). new MyClass = class {}

D). create class MyClass {}