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.
Such aircraft are most often operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an aircraft intended for carrying multiple passengers or cargo in commercial service.he largest airliners are wide-body jets. These aircraft are frequently called twin-aisle aircraft because they generally have two separate aisles running from the front to the back of the passenger cabin. These aircraft are usually used for long-haul flights between airline hubs and major cities with many passengers.