(30 marks) Gage Irwin (GI) is a text book publisher. GI sells to bookstores for $60 per book. Each book costs $40 in print costs. The authors make $10 in royalties on each book sold. Advertising and marketing costs are $100,000 per title. Gage Irwin is thinking of creating an e-book for one of its titles. An e-book will have no printing costs but will have an additional fixed cost of $50,000. Comparable e-books sell for $40 each. Require: SHOW YOUR WORK FOR EACH b) (10 marks) Calculate the unit contribution margin in dollars that Gage Irwin makes on each printed textbook. c) (10 marks) Calculate the number of print textbooks Gage Irwin must sell in order to break even. d) (10 marks) Calculate the number of e-books Gage Irwin must sell in order to break even