I can recommend the book by John Vacca that came out a while back, but it lacks biology and chemistry problems to some extent. A website would serve as an online bank.
Buy The World’s 20 Greatest Unsolved Problems by Vacca, John R. (ISBN: 9780131426436) from Amazon’s Book Store. Everyday low prices and free delivery on eligible orders.
I can recommend the book by John Vacca that came out a while back, but it lacks biology and chemistry problems to some extent. A website would serve as an online bank.