76. Some gas is 2 kg at a temperature of 300 K under a pressure of 0.5 MPa. As a result of isothermal compression pressure is increased threefold. Jobs spent on compression, A = -1.37 kJ. Define:
1) What is a gas;
2) the initial gas density.

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)