You are designing a system to run a bookstore. revenue for the store comes from two distinct services: customers can purchase books, or bring their books in for rebinding. you are considering making a separate class for each service, both of which would be subclasses of a general "sale item" class. what are the likely benefits of such an approach? are there any possible arguments against using inheritance in this case? be sure to specify what factors could influence your decision.

A2-m rigid tank initially contains saturated water vapor at 100 kpa. the tank is connected to a supply line through a valve. steam is flowing in the supply line at 600 kpa and 300 c. the valve is opened, and steam is allowed to enter the tank until the pressure in the tank reaches the line pressure, at which point the valve is closed. a thermometer placed in the tank indicates that the temperature at the final state is 200°c. determine (a) the mass of steam that has entered the tank (b) the amount of heat transfer.