Using the principles of third degree price discrimination and profit maximization with third degree price discrimination, please solve the below problem:
On Amazon.com, there are three versions of Keynes' famous General Theory: a hardcover for $20.48, paperback for $9.16, and a Kindle version for $1.00. There is not much difference in the cost of production between hardcover and paperback books (though there likely is for the Kindle e-book version), but hardcover books do tend to be published earlier than paperback versions of the same book. How do you explain the wide variety of prices for basically the same book?