With Best Regards: Closing Your Letter. June 17, 2014 by. When writing professional or informal emails and letters, it is often considered proper etiquette to complete your correspondence with an appropriate closing signature.
What two conditions are needed for clouds to form? Air must be cooled to its dew point and particles must be present in the air When are clouds formed by ice crystals instead of drops of liquid water?
Clouds are formed in two ways. (1) Air, in which water vapor is present, is cooled to its saturation point and condensation occurs. The cooling process will occur as warm air comes in contact with a cold surface or with a surface that is cooling by radiation or as air is affected by adiabatic expansion.