Obed Corp. makes three models of high-performance cross-country ski machines. Fixed expenses per month total $185,820. Current operating data are summarized below: (Total 13 Marks) Myski Yourski OurSki Selling Price/Unit 400 $ 500 LA 250 Variable Cost/Unit 100 $ 200 150 Monthly Sales Volume 600 400 500 Required: a) Calculate the contribution margin ratio for each product. (present all of your calculations) (4 Marks) b) Calculate the firm's overall contribution margin ratio. (present all of your calculations) (3 Marks) c) Calculate the firm's breakeven point in sales dollar. (present all of your calculations) (3 Marks) d) Calculate the firm's operating income. (present all of your calculations)