4. A refrigeration system using refrigerant 22 (R-22) is to have a refrigerating capacity of 80 kW. The cycle is a standard vapour compression cycle in which
the evaporating temperature is -8°C and the condensing temperature is 42 C.
Show the cycle on both T-s and p-h diagrams.

In a unit cell of fcc structure, indicate the position of one of the tetrahedral interstitial sites by plotting the corresponding tetrahedron. do the same for one of the octahedral interstitial sites (in a separate fcc unit cell). mark the positions of all the tetrahedral and octahedral interstitial sites in the unit cells. how many equivalent tetrahedral sites and how many equivalent octahedral sites are contained in a fcc unit cell, respectively. what is the coordination number for a tetrahedral site and what is the coordination number for an octahedral site?