1 In a bowl, sift together the cocoa, baking soda, flour and salt. 2  Take a large mixing bowl and stir together the margarine and sugar, until you have a fluffy mixture. 3  Add the eggs one by one, mixing well in between.  Add the vanilla extract and continue mixing.
The airline industry became a systems-oriented world. Actually, the industry is a complex system defined by the interactions among its several sub-systems: aircrafts, airports, passengers and aviation policy. It is also a complex system in the sense that it encompasses several simpler sub-systems.
During much of its development, the global airline industry dealt with major technological innovations such as the introduction of jet airplanes for commercial use in the 1950s, followed by the development of wide-body âjumbo jetsâ in the 1970s.