Sometimes the temperature does not decrease with height in the troposphere, but increases. Such a situation is known as a temperature inversion. Temperature inversions limit or prevent the vertical mixing of air.
Middle range machines can cost on average $400 and are often multi-function with copier and laser printer capabilities. Finally, high-end machines which offer high speeds, high capacity and high resolution come at a higher price-expect to pay $1000 - $2500 for such a fax machine.
Fax machines are a common instrument used in businesses throughout the world and a very convenient way to send paper documentation. In 1989, the U.S. Postal Service introduced a fax service for citizens to use. Today, this service is available in most post office locations throughout the country.ax machines are a common instrument used in businesses throughout the world and a very convenient way to send paper documentation. In 1989, the U.S. Postal Service introduced a fax service for citizens to use. Today, this service is available in most post office locations throughout the country.