What does Object.keys(obj) return?

How do you access a property called 'name' from an...

A). person.name

B). person['name']

C). person->name

D). person::name

How do you get the number of properties in an obj...

A). Object.keys(book).length

B). book.countProperties()

C). book.totalProperties()

D). book.length()

How do you iterate over all properties of an obj...

A). for (var prop in person)

B). forEach(prop in person)

C). for (var prop of person)

D). forEach(prop of person)

How do you add a method to an object created wit...

A). this.methodName = function() {}

B). this.methodName: function() {};

C). this.methodName = () {}

D). this.methodName: () {}

What happens if you access a non-existent property...

A). It returns undefined.

B). It throws an error.

C). It returns null.

D). It returns true.

What will console.log(obj.toString()) output?

A). The string representation of...

B). The object itself.

C). An error.

D). 1

How can you remove a property 'email' from an obj...

A). delete user.email;

B). user.remove('email');

C). user.email = null;

D). user.pop('email');

What is the purpose of the 'super' keyword in a ...

A). It calls methods from the paren...

B). It creates a new instance of the...

C). It refers to the current object.

D). It checks for property existence.

How do you check if an object has a property 'col...

A). 'color' in obj

B). obj.hasProperty('color');

C). obj.contains('color');

D). obj.propertyExists('color');

What is the correct way to create an empty object...

A). var obj = {};

B). var obj = ();

C). var obj = [];

D). var obj = <{}>;