The following is the stockholders' equity section of Harbor Co.'s balance sheet on December 31: Common stock $10 par, 100,000 shares authorized, 50,000 shares issued of which 5,000 have been reacquired, and are held in treasury $ 450,000 Additional paid-in capital common stock 1,100,000 Retained earnings 800,000 Subtotal $2,350,000 Less treasury stock (150,000) Total stockholders' equity $2,200,000 Harbor has insignificant amounts of convertible securities, stock warrants, and stock options. What is the book value per share of Harbor's common stock?