please explain

9.25 NRV Method, Contribution Margin, Further Processing for a Service Deluxe Tours, a tour organizer, leased a cruise liner for a special around-the-world tour. The 02 03 LO4REQUIRED lease cost is $200,000. Two classes of passengers are booked on the tour: first class and economy class. The total revenue from the 100 first-class passengers is $200,000 and from the 200 economy-class passengers is $200,000. Other costs for the two classes of passengers amount to $30,000 for first class and $30,000 for economy class. A. How much of the lease cost will be allocated to first-class passengers if the net realizable value method is used? B. What is the contribution margin generated by first-class passengers? C. When the cruise liner managers are deciding whether to increase the number of first-class rooms, which joint cost allocation method is best to use? Explain