(recommended project: combining composition and inheritance) in this chapter, we created the commissionemployee– inheritance hierarchy to model the relationship between two types of employees and how to calculate the earnings for each. another way to look at the problem is that commissionemployees and are each employees and that each has a different compensationmodel object. a compensationmodel would provide an earnings method. subclasses of compensationmodel would contain the details of a particular employee’s compensation: —for employees compensationmodel subclass would contain grosssales and commissionrate instance variables, and would define earnings to return grosssales * commissionrate.

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.