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 will either be composed of ice or water droplets depending on the height of the cloud and the temperature of the atmosphere. Because the droplets are so small, they can remain in liquid form in temperatures as low as -30 Â°C. Extremely high clouds at temperatures below -30 Â°C are composed of ice crystals. Clouds form when the invisible water vapour in the air condenses into visible water droplets or ice crystals.