What is the result of let x = 10; x -= 3;?

How can you swap the values of two variables a and b in one line?

A). [a, b] = [b, a]

B). a = b, b = a

C). a == b, b == a

D). a === b, b === a

How to use destructuring to extract properties from an object?

A). { a, b } = { a: 1, b: 2 }

B). let { a, b } = { a: 1, b: 2 };

C). let a, b = { a: 1, b: 2 };

D). let (a, b) = { a: 1, b: 2 };

What does let { a: alpha, b: beta } = { a: 1, b: 2 }; do?

A). Creates variables alpha and beta with values 1 and 2

B). Creates variables a and b with values 1 and 2

C). Throws an error

D). Assigns default values

What will be the result of let { a, b } = { a: 3, b: 4 };?

A). a is 4, b is 3

B). a is 3, b is 4

C). a is undefined, b is undefined

D). a is null, b is null

What does const do in JavaScript?

A). Declares a block-scoped variable

B). Declares a constant value

C). Declares a global variable

D). Declares a function

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

A). 5

B). 10

C). 15

D). 20

How do you assign default values in destructuring?

A). let { a, b } = { a: 1 };

B). let { a = 1, b = 2 } = {};

C). let [a, b] = [1, 2];

D). let { a, b } = { a: 1, b: 2 };

What is the equivalent of x *= 4?

A). x = x + 4

B). x = x / 4

C). x = x * 4

D). x = 4

What will const x = { a: 1 }; x.a = 2; do?

A). Throw an error

B). Change x.a to 2

C). Change x to 2

D). Do nothing

What will let x = 5, y = 10; [x, y] = [y, x]; do?

A). Nothing

B). Throws an error

C). Swaps values of x and y

D). None of the above