How Much Do Diamond Engagement Rings Cost. There are two major factors which contribute to the cost of a diamond: a ratings system called the âFour Csâ and whether or not the diamond is ASG/GIA certified. The Four Cs refers to the diamondâs color, cut, clarity, and carat size.
Best Answer: A wind vane is used to tell wind direction. The National Weather Service and those that have a lot of money use a Aerovane. Aerovanes are commonly used at many weather stations and airports to measure both wind direction and speed.
A windmill anemometer is a common instrument used at weather stations to obtain the wind speed. A wind vane is used as part of the anemometer to determine the wind's direction. As the wind flows over the windmill, the speed and direction of the wind can be measured with this instrument.