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?
High clouds (Family A) These generally form above 16,500 feet (5,000 m), in the cold region of the troposphere. In Polar regions, they may form as low as 10,000 ft (3,048 m); they are denoted by the prefix cirro- or cirrus. At this altitude, water frequently freezes so clouds are composed of ice crystals.