What's one difference between the async and defer attributes of the HTML script tag?

The following program has a problem. What is it? var a; var b = (a = 3) ? true : false;

Which collection object allows unique value to be inserted only once?

How does the forEach() method differ from a for statement?

Which choice is an incorrect way to define an arrow function that returns an empty object?

USERNAME and userName

The `else` statement is ___

What does isNaN() do?

Properties of a RegExp object include:

Properties of objects may be accessed using...